Scribe Post for October 29, 2009

Thursday, October 29, 2009
Hello everyone. Today in class we had a couple of guests. They just observed us learning. In the beginning of the class Backe asked me one of the things we did from last class. I said a negative plus a negative equals a positive (-) + (-) = (+). I was wrong and Angela corrected me. Did you know that when two positive numbers are added they can never equal a negative number? When you add a negative and a positive number the outcome depends on the numbers.


Here are some examples.



As you can see the positive number is higher than the negative number. So the answer for it will always be positive.






Although for this one, the negative number is higher than the positive number the outcome will always be a negative number.




A key thing to remember about this unit is zero pairs,
Zero pairs are when a positive and a negative number cancel each other out.

Take a look at this as a memory refresher.










If you look to the left, the numbers have the same denominator. So you only have to compare the numerators.

10/6 is larger because it has more pieces out of a whole the 9/6.



If you look to the left (again) the numbers have the same numerators so you compare the denominators.

3/4 is larger than 3/5 because if you cut up both of these fractions you would see that 3/4 takes up more space than 3/5.


Today's home work is to do Page 57, 58, and 59 Show Your Know and Check Your Understanding. (You only needed to read page 58). You also have to look up Absolute Value.
And the last little bit is to find out if these equal a positive or a negative.











I hope you learned a little bit from my scribe. And the next scribe is........Liem. Yep you get to do a weekend scribe. Also if anyone found any errors please feel free to comment so I can fix them.


P.S if anyone has troubles putting a video in their post try adding

as it appears at the end of your video embed code.
(Blogger didn't let me put the code to make the videos work in)

If anyone has some trouble with Absolute Value take a look at this video I found.

Scribe Post for October 28, 2009

Wednesday, October 28, 2009
Hello everyone! Nicky here to tell you about math today. The first thing Mr. B said today was that I stole textbook #11.... Yeah.... But I most certainly did not! He had it the whole time! Ahem, where was I? Oh yes, math class. Well, in math today we played a card game. Now, just in case if you want to play it at home, Data will now recite the rules in his anroidic manner.

Thank you Data, your help is always appreciated. So, we played that game for a good portion of the class and this Mr. B made us get out those great study guides, foldables! Sadly, he made us add things to it...and he wasn't very specific... But, that's where your brain comes in. For homework our job is to fill out the 1st square in our foldables (which should say Rational Numbers, hint hint). Now, by the 1st square I mean the square that is on the top left (for all you chess players it'd be A4...). So, just make sure you write it under the 1st square.

However, that isn't all. In our definitions foldable we have to write some more stuff (yes I know...how fun). So, just what do we have to write? What numbers belong to each group. Eg. Under Natural Numbers you would write Integers. BUT, that is not all. Mr. B also gave us some very "smarticle" things to write as well. These are as follows. Oh DATA!!!

Thank you Data for telling the nice people the smarticle things. Ahem, now...hm...what else did we do? Ah, yes. Mr B. gave us some equations. All we have to do is say whether the answer is positive or negative and then we have to explain how we know. Here are the equations.

Well, that's about it. I will now list the homework in BOLD BRIGHT COLORS, for those who don't want to read my entire scribe.

Homework
Blue+White Foldable (Rational space, put "stuff" inside)
Definitions Foldable (Middle Column)
Questions (Explain why negative or positive)
Go to E-Book (Complete Show You Know Chapter 2.2)

There you have it! Our math class in a nutshell. Please do your homework (*cough* THE CLASS *cough*). The next scribe will be *drum roll* VIKRAM!!! *trumpet fanfare*

Remember, only you can prevent forest fires!

Scribe Post for October 27, 2009

Tuesday, October 27, 2009
Hey 9-05! Abby here with today's scribe post! First of all, I'd like to congratulate us 9-05 people. I think we did a really good job on the blog posts we've been doing.. So let's keep it up!

Okay, so today in math class, we went to the computer lab. First, we went over our homework from yesterday. I think some of us had a hard time with finding a fraction for a repeated decimal number with 3 numbers after the decimal. So here is the rule:













For this rule, you always want to multiply out all the repeating. So 0.2 repeated has to be multiplied by 10 to move the decimal down 1 place value. 0.43 repeated has to be multiplied by 100 to move the decimal down 2 place values, and 0.172 repeated has to be multiplied by 1000 to move the decimal down 3 place values.

x = o.2 (repeated)
10x = 2.2
9x/9 = 2/9
x = 2/9

x = 0.43 (repeated)
100x = 43.43
99x/99 = 43/99
x = 43/99

x = 0.172 (repeated)
1000x = 172.172
999x/999 = 172/999
x = 172/999


After that stuff, the people who needed help with the chessboard question went to the hallway with Mr. Backe so he could explain it to us. Here, I will explain and show you how to start the chessboard question.

1. A chessboard is a large square and is made up of 64 small squares. Consider only the first three rows of the chessboard.

a) Find the diagonals of all squares and rectangles possible in the first three rows. Arrange the squares and rectangles, from least to greatest, by length of their diagonals.

So first, we look at the first square on the chessboard:

Figure 1.0
















So, to find the diagonal for square number one, we have to use the
a2+b2 = c2 formula. For the square, the dimensions are 1 by 1.

This is how you find the diagonal for square number one:

a
2+b2 = c2
12+12 = c2
1+1 = c2



1.414 = c



Now, I'll show how to do the second part:

Figure 1.1















For the second square, we use the exact same formula, but the number change. B changes into 2 because the sides, which are all equal, are 1. And so, 1 side + 1 side = 2 sides. Or, to make easier 1+1=2!:
a2+b2 = c2
12+22 = c2
1+4 = c2



2.236 = c


Then, we have to do the rest of row number 1, which is the same procedure. When you go up one square, the b changes because the number of bottom sides are adding up. The a stays the same, and the hypotenuse grows larger. (I'm not sure if I made sense there..)

Figure 1.2







(sorry if the image is blurry!)


The second row has the same procedure except for the first diagonal because we already figured it out in row 1! (refer to Figure 1.1)

Figure 1.3











The third row ALSO has the same procedure
except for the first diagonal because, like the second row, we already figured the first diagonal for the third row in row 1 (refer to Figure 1.1)

Figure 1.4









For the rest of the class, we went on mathlinks9.ca and shodor.org. In Mathlinks9.ca, we checked out some websites under student center; chapter 2; weblinks. Also, Mr. Backe told us to read a bit about Neil Barlett. On shodor.org, we did some games on fractions.

HOMEWORK:
-play some fraction games on shodor.org
-fill in math journal

Thanks for reading! If there's anything on here that doesn't make sense, or seems wrong, please comment and I'll try my best to correct my mistakes! Okay everyone, have a good evening!

The next scribe I choose for tomorrow is.. Nicky!

9-05, the "CLASS" of 2009-2010

Monday, October 26, 2009
Heeeyyy 9-05 ! Do you guys remember one of our best students in class' post? Ahem DEAN ! If you forgot or didn't see it, it said something about us being "the class". I know Mr. Backe is proud of us because we are doing all our work and we are doing our job in the blog and everything else. Especially our daily commentors - Dean, Linda, Kara, Melissa, Joseph, sorry if I didn't mention your name... just tell me (: You guys are doing so great and for all the people who do their work all the time, going to our home page to check out Mr. Backe's assigned work and posting it for other people to see, you are doing awesome and keep it up! We are the "class" ! I was checking out the blog today and looking at all the post and I was just thinking that whoever sees it will be soo impressed because you guys did such a great job and keep it up and make Mr. Backe proud. This is our last year at Sargent and let's make it the best. Other classes are awesome too, 9-02,9-04 and 9-06. And again keep up the good work and let's keep on impressing people and making Mr. Backe proud. 9-05 FTW, going to be "THE CLASS" of 2009-2010. This is our year, let's make the best of it :D

Sincerely Yours,
Karen (:

-you might think I'm a loser for doing this, I was bored so I decided to check out the whole blog and was so impressed with the things that I've seen and I wanted to pass out the message !

Scribe Post for October 26, 2009

Hello there 9-05! (: First things first, I would like to say HAPPY BIRTHDAY JOSEPH! Anyways, the first thing we did in class today was we went over questions that we did not understand.

One of the questions that was asked was, how can you put -1 1/2 into an improper fraction when there is a negative integer?
Well, as you can see, I put the negative signs red. The reason why I did that is because first, we solve the question without the signs then we add it on afterwards. The first thing we do is we add the whole number (1) to the denominator (2) and that equals to 2. Then, we add the 2 to the numerator (2) which equals to three. Since we are making this into a proper fraction, we add the denominator. Which the answer equals to 3/2. Now that we have solved everything, all we have to do is add the negative signs.

After that, Mr. B asked us to change 0.16 (16 is repeating) into a fraction. The answer we got was 16/99. Do you know why? Here, I will show you.

Do you get it? Well, to find the fraction of it you have to times it by 100x. We do that because a fraction is out of a hundred, and the "x" stands for the number we are trying to find. The reason why we use the number 16.16 is because we have to move units down because of the 100.
(I'm sorry if you dont understand, I'm bad at explaining.. but I will try my best to help you)Then 100x-x = 99x. You get the the answer 99 because when you have 100 bananas for example and you take one away there are 99 bananas. The "x" does not change anything, the "x" represents as 1. Then the 99's cancel eachother out and then it becomes x=16/99. If you want to make sure it is correct, you can check it with a calculator to see if the answer is really 0.16 repeating.
Here are other examples of what we did in class:
0.23 (repeating on 23)
0.16 (repeating on only the 6)
You are probably wondering how to do this right?
Some of the possible answers are: 16.5/99, 6/9. 1/6. 16/9.
Which one is the correct answer?
Let's see. 0.016 (16 is repeating)
What is the answer?
16/990 or 16/999?
Homework:
Find the Fractional Expression for these numbers.
0.2 (repeating on the 2)
0.43 (repeating on 43)
0.172 (repeating on 72)
How to find the answer to:
3/5 - 3/8=?
AND
of course Math Journal .

AND... just because we are "THE CLASS", here is a video if you are still having trouble (:
oops. nevermind. I can't seem to find anything... because when I looked for a video, it says instead of 100x, its 10x.. I don't really understand why.. but I will ask Mr. B tomorrow (:
Well, I hope you guys enjoyed reading my post.. I am sincerely sorry for not posting the part about the chess problem. I don't understand it and plus, I have to study for french. So, I'm very very sorry. I appreciate your time looking at my work and comment if you'd like (: OH! I almost forgot, the next scribe is...... ABBY ! (:

Scribe Post for October 22, 2009

Sunday, October 25, 2009
Hello, 905. This post will talk about most of the things we talked about in class.
PURPLE - indicates a key term. (it would be best to remember this).

The first thing Mr. Backe wanted us to do was a question that looked like this:
We had to insert a sign in the middle that made the statement true. ( > is greater than, < is less than, = is the same.) First you would need to find the lowest common denominator (LCD) How you do that, is by multiplying the two denominators. So .. 7 (9) = 63. 63 would be the LCD. Remember, what you do to the bottom, you do to the top. <-- (Remember this for ratios later on.) Now you need 3 (9) = ? and for the other fraction 4 (7) = ?. The first answer would be 27 and the second one would be 28. Put all of the answers together and it would be WAY easier to compare. Your end result should look like the second picture. Why does this work? Because the fractions on the left and the fractions on the right are equivalent fractions. The only difference is that one is showed in simplest form.



Next, he wanted us to find numbers that fit in between 0.3 and 0.4. Also for 0.25 and 0.45. The number 0.35 would fit in between for both. A LOT of numbers would fit in between. An infinite amount of numbers. Meaning the list is endless. Mr. Backe also wanted to know which has more numbers in between. We all know it has an inifinite amount in between, BUT what we had to do was find the range of the numbers. You find range by subtracting the smallest number from the biggest number. So .. 0.4 - 0.3 = 0.1. And 0.45 - 0.25 = 0.2. The second set would have more numbers because it has a higher range. Remember, even if there is an infinite amount of numbers in between, the one with the larger range would have even more than that.

PS. At the end of class he gave us 3 signs. %, ¢, and $. What do these all have in common? Percent, 1 cent, 100 cents. Hmm, CENTS. They all have the word cent in it, which if you didn't know means 100.

Homework Check:
2.1 - CYU pg. 51 #1, 2, 3.
Practice pg. 51 # 4 OR 5
8 OR 9
10 OR 11
12 OR 13
15 AND 17.
Apply pg. 52-53 # 18 OR 19
# 20, 22, 23,24, 26
Extend 29 OR 30.

JOURNAL! Make sure your completing this daily, that's what the scribes are for! Anyways, sorry for this scribe being late, but comment and tell me if i made any mistakes! Next scribe will be, -DRUM ROLL- MELISSA! Have fun doing your scribe. Good job 905 for all the hard work we've been doing this whole time.

October 21, 2009 Scribe Post

Wednesday, October 21, 2009
Hey 9-05! *cough, The Class* Today in class we did some more learning about Rational Numbers.

Can you prove that pi is an irrational number? Well, that's one thing that we learned in class today. On your calculator put in: π then =. You should get 3.141592654. Now divide π by 100000000. *gasp* Did you get pi as an answer? That's because there are a limited amount of characters on your calculator and it can't calculate the full number.

Today we also learned about Equivalent Fractions. Equivalent Fractions are fractions that mean the same thing. In other words have the same value in decimal form. An example of an equivalent fraction is 10/20=1/2=5/10=100/200=0.5

Sometimes when we see something written differently we almost automatically think that they are different from each other. There are many different ways to write the same fraction. So, next time you compare fractions..check to make sure they aren't equivalent.

Example:











REMEMBER: The sum of opposites=Zero. Why? Because they are Zero Pairs, which means they cancel each other out. 365+(-365)=0


WATCH THIS VIDEO IF YOU HAVE ANY PROBLEMS:





HOMEWORK:

  • Mr.Backe gave us a package of papers a few days ago. We need to complete Section 2.1 Extra Practice(2 pages)

  • In the homework book. Chapter 2.1 (pages 16-17)

  • And remember to Journal everyday we have class.

By the way, if you're planning on buying a new calculator..Casio fx-300Es is the best one for Grade 9. hmm...The and the next scribe is........Dean S...!!!!..gets a longweekend..

Okay, well this is the end of my scribe..I hope I didn't miss anything. Please leave a commment for any reason.

Scribe Post for October 20, 2009

Tuesday, October 20, 2009
HEEY 9-05 ! We didn't really do much today in class but do foldables for our new unit in math, Comparing and Ordering Rational Numbers. If you missed class today or didn't get the foldables done here it is: So, Backe gave us 6 pieces of paper, 2 big white one and 4 normal size blue ones. He asked us to fold them and do whatever it is in pg 44 in the math text book, mytextbook.ca.

Here is a picture of what it's supposed to look like, it's mine:


































How did I do this?
I used my big white piece of paper and folded it in threes equally. I took 2 pieces of blue paper and folded it in threes and then fold it in half and I folded the other 2 like a hotdog and glued it to the white paper.

After that, we had to fold the other whiter paper in threes and then fivided it in 6 sections like this:

*I know you can't really see this because it was too bright. It's supposed to be divided in 6 and you're supposed to write these words on each section/box and then the definition of the words behind that page and then numbers that belong and don't belong.
- Natural Numbers - Irrational Numbers
- Whole Numbers - Real Numbers
- Integers
- Rational Numbers

























I don't really know how to show you right but this is the best that I could. You put the numbers that don't belong at the back of numbers that belong.

I guess that's it. Don't forget to put the definitions, numbers that belong and don't belong again.

That's it! If I forgot something or made a mistake don't forget to point it out and don't forget to comment and tell me what I could've done better.
JOSEPH (JD!) you're next scribe. :D YOU'RE WELCOME!

9-05 commentors,
THANKS for all your comments and I changed the things that you told me to do so that it's better for you guys. (:

Rational Numbers

Monday, October 19, 2009
As you all know, our next unit is rational numbers.

Rational Numbers are numbers that can be expressed as a fraction. The denominator cannot be equal to zero.

Natural Numbers are numbers we use every day
example: 1, 2, 3, 4, 5, 6, 7, 8, 9
They are also called counting numbers.

Whole numbers are 0 and the natural numbers.

Integers are whole numbers and their opposites.
-3, -2, -1, 0, 1, 2, 3

As said earlier, rational numbers are numbers that can be expressed in fraction form. Irrational numbers cannot be expressed in fraction form.
Like PI and the square root of 3

Then there are real numbers. Real numbers are numbers we normally use, including rational and irrational numbers, fractions, decimals, and integers.

Just because I was curious, I searched up what imaginary numbers are. To put it simply, its a number that when squared gives a negative result.

Well that's all. Please be a good person and comment! But I won't hold it against you if you don't. :)

Scribe Post for October 19, 2009

Hi 9-05! Today in class we did a lot of things. First of all we got our surface area tests back, and let me tell you we were ALL pretty shocked to see how we did (including me). I guess that just means that we have to study a little harder next time, RIGHT 9-05!

When he handed our tests back we had to hand in our stash-it's at the same time, so I hope that you all did that and it was completed!

We got this BIG package full of questions about rational numbers for our new unit, which is obviously on rational numbers. It also included a self-assessment, and we were supposed to fill out the before section of 2.1.

After that we took some notes on RATIONAL NUMBERS. We found out that a rational number means:

-Any number that can be expressed as a fraction A/B where A and B are integers and B doesn't=0

We made a diagram that looked something like this:




IRRATIONAL NUMBERS- cannot be expressed as fractions. Examples of this are: √3 and π (pi)

That was pretty much all that we learned today.
I found a website that you may want to go to, it will help you to figure out what we will be learning about in this unit, in case you are already confused.

Here is the link: http://encyclopedia.kids.net.au/page/ra/Rational_number

For homework you DON'T HAVE TO DO JOURNAL! We didn't get our journals back, so don't worry about it. You also have to get your test signed, and the GET READY section of your workbook (pg 14-15) The workbook part is really easy, mostly reading and a few simple integer questions.

I pick Karen for the next scribe. PLEASE comment :]

Rational Numbers

Our Next Unit Is Rational Numbers. What are they? How do we use them?

A Rational Number is any number that can be expressed as the quotient a/b of two integers.

So A number that can be a fraction, an example would be maybe



Natural Numbers are first they are numbers that we use everyday like 1,2,3,4,5,6,7

Then it is Whole Numbers 0 and Natural numbers.

Then Itegers which are Whole Numbers and their opposites eg. -3,-2,-1,0,1,2,3

Then it Rational Numbers itegers that can be expressed as fractions.

After that Irrational numbers, numbers that can't be expressed as fractions. Eg PI.

Ok so, I hope i covered some major things.

Elegant Algebraic Formulas

Sunday, October 18, 2009
Hi, again... this is going to be my second post for today and it's going to be about the most "Elegant Algebraic Formulas" to use for finding the surface areas for certain shapes.

The most elegant algebraic formula for find the cube's surface area is S.A=6s², because there are 6 faces and each side is a certain measurement.

The best or I mean the most elegant algebraic formula for finding the Surface area for the Rectangular Prism is in the picture below..


And Finally the elegant algebraic formula for finding the Surface area for the Cylinder is again, located in the picture below...



Rational Numbers

Well I guess I'm really lucky because I didn't really know about this part of the homework for the weekend, so that little gut feeling saved me there. Since we did our test, that means that were starting a new unit which is most likely the so-called "Rational Numbers". I'm pretty sure that we learnt this last year but I obviously forgot, but I looked it up.

Rational Numbers- Means that specific numbers that can be written as a fraction or ratio with 2 integers. An easy example is 5, five can be written like so= 5/1.

(Just so you know)Integers- Integers are all whole numbers and their opposites like 1,2,3,4,5 or -1,-2,-3,-4,-5 (got the definition from Mr.B's comment on Joseph's Rational Numbers post)

Irrational Numbers- The absolutley opposite meaning of Rational Numbers. An example you can try out is the square root of 7 because the decimal keeps going on and on. Which means you can't write a ratio or fration with irrational numbers.

Question 11

11. List places or situations in which surface area is important. Compare your list with those of your class mates.


1.) When designing clothes.

You need to know the measurements for the people you are making the clothes for.


2.) When wallpapering your wall/ or painting a wall.
You need to know the dimentions of the wall you are covering to buy the right side.


3.) When buliding a house.
You need to know the size of what you are building, so you can buy the correct amount of materials.


4.) When buying furniture.
You need to know the measurements of you room, to buy the correct size furniture.


5.) When designing shoes.

You need to know the size shoe you are making.

6.) When buliding a wall.
You need to know what the measurments are, also the surface area.



7.) When you are a Carpenter
You need to know surface area, of areas where you are expanding or doing work on.

8.) When you are a farmer.
You need to know the area of your field so you can buy seeds.

9.)When you are putting shingles on your roof.
You need to know the surface area of your roof.

10.) When you are landscaping your backyard.
You need to know the surface area of your yard, for the right amount of plants or grass.

11.) When you are wrapping gifts.
You need to measure how much wrapping paper it takes to cover the surface area of the present.

12.) When you are baking layered cakes.
You need to know the surface area of the first layer so you can make the next layer smaller, etc.

13.) When you are buliding a treehouse.
You need to know the measurements of the tree, plus the surface area of the house to make sure it will fit.

14.) When you are laying a floor.
You would need to know the surface area of the floor.

15.) When you are buliding a deck.
You would need to know the suface area of the spot where you are placing it.

Rational Numbers

Heey 9-05! In case you guys don't know, Mr. Backé assigned us to post a blog about the term “Rational Numbers” mean and where it came from. Not that hard. Just search it online and type it here and publish. Oh, and you can also put a few examples. (:

Rational numbers are numbers capable of being expressed as an integer or a quotient of integers, excluding zero as a denominator.

e.g.
1.75 because it can be written as 7/4
0.001 because it can be written as 1/1000

Irrational numbers is a number that cannot be written as a simple fraction - the decimal goes on forever without repeating. It is called irrational because it can't be written as a ratio or fraction.
e.g. pi or π is irrational because the value is
3.1415926535897932384626433832795.....

Question #11

List places or situations in which surface area is important:

Buying a house or renting an area - apartment, space, etc.
*In case you need to know how big is the house or space. People usually needs to know the size of the rooms for them to pay for it and buy it.

Painting a room or a house.
*You need to know how much paint you're going to buy and use to paint whatever space you need to paint.

Buying a table.
*You first need the area of the space where you're going to put the table and then the area of the people so you know if it's going to fit in the space.

Buying carpet.
*You need the are of the space where you're going to put the carpet and how much carpet you will need to cover up the space.

Growing grass.
*If you're planning to grow grass in let's say your backyard with no grass at all and you want to cover it all. You have to know the area of your backyard to know how much grass you will have to put on it to cover it.

Building a house.
*You need to know the area of the lot (space where you're building the house)

Putting curtains or blinds.
* You need to know the area of the window you're going to cover and the (size length and width) of the blinds or curtains you need.

Tiling pools .or washrooms.
* You need to know the area of the washroom and the number of tiles you need.

Making a dress or any kinds of clothes for someone.
* You need to know the measurements of the person and the amount of fabric you will need.

Baking (brownies, cakes, etc.)
* You need to know the size of the pan, especially when your baking or making something that needs a baking pan. You need to know the size of the baking pan.

Building a pool.
*You need to know if the pool will actually fit and like how much you're going to dig for it to fit. You also need to know how much water you're going to put in the pool.

Wrapping presents.
*You need to know how much you're going to have to wrap and how much you need to cover it up.

When you're planning to decorate a space for a celebration.
*You need to know the area of the space you need to decorate to know how much decorations you need.

Watering plants.
*You need to know the size of whatever you're watering (for example: your lawn), you need to know how much water you need to water the whole thing.

Putting fertilizer on your plants.
*Just like watering your lawn. If you want to cover the whole lawn with fertilizer you have to know the size of your lawn to know how much fertilizer you need.

Road Trip.
*There are lots of examples here where you need to find area. First is the car, if you have lots of people and you are bringing lots of stuff with you, you need a car that will fit the car and to know how much stuff you can bring and how many people can go. Second, is the distance to where you are going.

Buying a cage or aquarium.
*You need to know the size and amount of animals you need to know what size of cage you're going to buy. You have to buy a cage that depends on how many pets you're going to put in it and the stuff that they need, like food and water bowl.

Rational Numbers

For some of you that didn't know yet, our next unit is on rational numbers. First of all, what is rational numbers?

Rational Numbers:
- A number that can be expressed as the quotient of two integers, where the divisor is not zero. Which means that a number that can be put into a simple fraction.

For example:
-half in decimal form is 0.50 and when it is written in a fract it is 1/2.

Irrational Numbers:
- The opposite of rational numbers. The number cannot be expressed as the quotient of two integers, where the divisor is not zero. Which means that you can't put a number into a simple fraction.

For example:
-a number that goes on and on and on and never stops, 0.12345678910111213141516...


I hope you like my post! (:

Elegant Algebraic Equations

Elegant Algebraic equations.


I didn't know what Mr. Backe was talking about when he said Elegant Algebraic Equations. And thats what they are, the most elegant way to find the surface area of a shape. So im going to tell you the different formulas for different shapes.





S.A of a Cube 6s²


Say the cubes side lenght is 7


S.A 6s²


S.A = 6(7²)


S.A = 6(49)


S.A= 294 u²


A rectangular Prism

S.A 2(lw)+ 2(hw) + 2(hl)

S.A 2 (4)(6) + 2 (5)(6) + 2(5)(4)


S.A 2 (24)+ 2(30)+ 2(20)


S.A 48+ 60+40


S.A 148u²






Cylinder

S.A 2pi r² + 2 pi rh

S.A 2 (3.14)(5²) + 2(3.14)(5)(20)

S.A 2(3.14)(25)+ 2(3.14)(100)

S.A 2 (78.539) + 2 (314.159)

S.A 157.078 + 628.318

S.A 785.396 u²







Triangular Prism

2 Triangles bh ( don't put divided by 2 because bh/2 is for one triangle I am finding for 2)

2 triangles (15)(10)

2 triangles 150u²
base of prism lw

base of prism (15)(20)

base of prism 300u²

2 roofs lw

first we need the side of the roof.

a² + b² = c²

10²+ 15²=c²

100+ 225 = c²

(sqroot)325= (sqroot)c²

18.027 = c

2 roofs lw

2 roofs (20) (18.027)

2 roofs 360.555 u²

Add everything together.

150u² + 300u² + 360.555 u²=

810.555u²




Rational Numbers

The next unit or chapter is about "rational numbers". What are rational numbers? What does the term rational numbers mean? I don't know most of these, so I read from the online textbook.

Rational numbers simply means numbers that can be written as a simple fraction. Example of a rational number is 8/4. The numbers in that fraction are the integers. Which is 8 and 4 (example). Rational numbers also means a ratio of 2 integers . One term we're all familiar with is integers, which we learned in grade 7, and grade 8. Integers are any whole number.

Irrational numbers are numbers that can't be written as a fraction. When you write it in decimal form, it goes on forever, without a pattern. An example of an irrational number is the square root of 7, or the value of pi. Both have decimals that go on forever, without a pattern. You also can't write both as a simple fraction.

Those are the major things I think we're going to learn in this chapter. Feel free to comment or add on to what I missed. :)

Elegant Algebraic Expressions

Hello everyone! I am making this blog post to show you the most elegant algebraic expressions for the surface area of a cube, rectangular prism, and a cylinder. I will also be answering some questions.

SURFACE AREA OF A CUBE = 6s²



S.A. = 6s²
S.A. = 6(2²)
S.A. = 6(2x2)
S.A. = 6(4)
S.A. = 24u²



SURFACE AREA OF A RECTANGLE = 2(lw)+2(lh)+2(hw)

S.A. = 2(lw)+2(lh)+2(hw)
S.A. = 2(5x6)+2(5x4)+2(6x4)
S.A. = 2(30)+2(20)+2(24)
S.A. = 60+40+48
S.A. = 148cm²

SURFACE AREA OF A CYLINDER = 2πr²+2πrh


S.A. = 2πr²+2πrh
S.A. = 2π(4²)+2π(4)h
S.A. = 2π(4x4)+2π(4)h
S.A. = 2π(16)+2π(4)
S.A. = 32π+8π
S.A. = 100.48+25.12
S.A. = 125.6cm²

COMPOSITE SHAPES
- a composite shape is a shape that can be divided into basic shapes, like a square, a rectangle, a triangle, etc.

This figure can be divided into two basic shapes, a triangle and a square.

HOW DOES SYMMETRY HELP US SOLVE SOME OF THESE SURFACE AREA PROBLEMS?
It helps us solve some of these area problems because some of the shapes have symmetry. Some shapes have sides that are the same, like, a square. all 6 sides have identical sides. If we know that there it has identical sides, then we can form a formula to solve the surface area of the shape.

WHAT HAPPENS IF A PART OF ANY OF THESE SHAPES IS MISSING? HOW DO I FIND SURFACE AREA THEN?
If there was a part missing in any of these shapes, you would have to calculate the missing area, and subtract it from the original shape.

THANK YOU FOR READING MY BLOG POST ! (: I hope this helps you learn more about surface area and please feel free to comment if I made any mistakes.

Question #11

11. List places or situations in which surface area is important. Compare your list with those of your class mates.

1) When you are designing a buliding.
-You need to know how many of a certain supply that you will need to finish the project. (eg. how much wood)

2) When painting a room.
-You need to know how much paint to buy based on how much it covers.

3) When (and if) you ever sew bed sheets.
-You need to know how much of the bed the sheets will cover.

4) When you are moving.
-You need to know how much space you will have for your furniture.

5) When you wrap a present.
-You need to know how much wrapping paper you will need based on the size of the present.

6) If you plan a wedding or other special event.
-You would need to know how much people and tables/chairs will fit into the rooms.

7) If you ever need to make ear warmers for an elephant.
-You would have to know the surface area of the elephants ears in order to make a hat.

8) If you are a clothing designer.
-You would need to know the size of the person to be able to make clothes that fit them perfectly.

9) If you decided to be a carpenter.
-You would need to know the surface area of people's floors in order to make carpets.
10) If you buy a door.
-You would need to know the measurements of the door frame so that the door would fit.

11) If you are writing an essay by hand.
-You would need to know how many pages that you would need based on how much you want to write.

12) If you ever decide to become anyone that teaches surface area.
-Well, obviously you need to know it to teach it!

13) If you are building out your backyard.
-You would need to know if you have enough space for a deck and pool.


14) When you are farming.
-You need to know if you have enough space for the amount of crops that you want, and if there is enough space for a certain type of crop that you may need more of.

15) When you are a real-estate agent.
-You would need to know if there is enough space for the amount of people that are going to live there.

Please comment!

Question #11

Surface area is very important. We use it in many different kinds of things. Here are some examples on when and where surface area is important.

1) When you want to become a math teacher.
- You would need to use those surface area skills, in order to teach surface area to your students.
2) When you want to become a baker or you just like baking cakes!
-You would need to find the surface area of the cake. So, you know how much icing you're going to put.




3) If you work in a packaging company.
- You would need to know how much material (eg. cardboard) you're going to use in order to pack your items.

4) When you're painting your house.
- Of course, you would need to know how much paint you're going to use! You don't just go to home depot or whatever, to buy random amounts of paint!

5) When you're building a book case/desk.
- You would need to know how much wood you're going to use.

6) If you're painting the bookcase/desk you just built.
- Again, you just don't go and buy random amounts of paint!

7) When you're changing the shingles on your roof.
- You would need to know how many shingles you're going to buy.

8) If you're going to put insulation in your attic or basement.
- You would need to know the surface area in order to know how much insulation you're going to use.
9) When you want to put drywall over that insulation.
-You would need to know how much drywall you're going to use.

10) If you're tiling your bathroom.
-You would need to know how many tiles you're going to use.
11) When you're buying blinds.
- You would need to know how big your window is. So, you have blinds that actually fits your window.
12) If you're planning to have a garden.
-You would need to know how much soil and fertilizers you're going to use.

13) When you want a pool in your back yard
-You want to know if the pool is actually going to fit.
14) If you have a diving board for your pool, you would need stairs for that.
- You would need to know the surface area of the stairs. So you know how much paint you're going to use.Paint the stairs with those grip paints, rustoleum, or what ever.


15) When you're buying a new fridge.
-You would need to know the surface area. So you know if it actually fits through your doors, and the actual spot it's going to be in the kitchen.

16) If you're buying new tires.
-You would need to know if the tires actually fits your vehicle.

17) When you're going to be an architect.
-You would need those surface area skills, so you know if your building will actually fit on the lot.

18) When you buy a Christmas tree.
-You would need to know the surface area of that tree, so you know it fits your living room.

19) If you're wrapping Christmas gifts, or gifts.
-You would need to know how much wrapper you're going to use.

20) When you're buying a tablecloth.
-You would need to know the surface area of the table, so the cloth fits.

Rational Numbers

The term "Rational Numbers" refers to the fact that a rational number represents a ratio of two integers. Rational Numbers are numbers that can be expressed exactly by a ratio of two integers. Or more simply put, a rational number is an integer that can be expressed as a simple fraction. An example of a rational number is 5 because 5 can also be expressed as 5/1, or 4 because 4 can be expressed as 16/4.
An irrational number is a number that cannot be written as a simple fraction and has a decimal that goes on forever without a pattern. An example of an irrational number is Pi - 3.14159265... etc.