### Scribe Post for May 27, 2010

Anyways, in class we went over Question #21 on Page 403 in the textbook.

*The radius is 3cm because the diameter is 6cm (double the radius)*

Now we need to find out the purple measurement, and since it's a right angle, we could use the "Pythagorean Theorem".

Now that we know the radius of the circle that's sticking out of the ice surface (2.82cm) we could find the circumference.

The circumference of the circle where the ball touches the ice surface is 5.6(pi).

The rest of the class was work period, and since the test was the next day, Mr.B was asked a lot of questions.

I hope everyone did good on their tests, and good luck on finding out your marks (:

Have fun with what's left of the weekend!

Good luck to all the track people who won't be at school on Monday, and those who will be here, let's have fun again :D

HOMEWORK:

- stashits ---> journal, test signed, 2 problems of the week (including #3)

The next scribe is Marc. I told him on Friday, and reminded him again today. He's doing the test scribe ... but he said he'll do it "laterz" ... so just wait for it (; haha .

### Scribe Post for May 20, 2010

Diameter - The distance across a circle through its centre.

Radius - A line segment joining the centre of a circle to the outside edge.

The angles ABC is called a Central Angle.

Central Angle - An angle form by two radii of a circle.

The straight yellow line from A to C is called a chord.

Chord - A line segment joining two points on the circumference of a circle.

Angles ADC and AEC are examples of Subtended Angles.

Subtended Angle: Lying opposite to.

Inscribed Subtended Angle: is equal to half the central triangle.

How do you find the measurement from B to C? Use Pythagoras!

First of all, why do we use Pythagoras? We can use Pythagoras method as long as there is a right triangle to find out the missing side length. Do you see the right triangle? If you flip it over or turn your head upside down, you will be able to see a right triangle. So, the angles AC will be represented as the hypotenuse which is c. And let's say that AB represents a and BC represents b.

a^2+b^2 = c^2

6^2+b^2 = 10^2

36+b^2 = 100

b^2 = 100-36

b^2 = 64

Square root b^2 = Square root 64

b = 8

The missing measurement of the line B to C is 8 cm.

Homework:

Chapter 10 Warm-Up #1

10.1 Textbook

-Practice, all odd

-Apply, all even

-Extend and any 2

10.1 Workbook

10.1 Worksheets

Well, that is all for now folks! (: I hope you enjoyed my post! Keep working hard 9-05! For exams are coming soon and we only got about a month of school left! The next scribe is KIM (:

Okay tootles!

### Scribe Post for May 25, 2010

*A tangent is:*

*-a line that touches a circle at exactly one point*

*-the point where the line touches the circle is called the point of*

*tangency*

*Pythagorean theorem (only if there's a right triangle)*.

*To find A*

*180°=A+42°+90°*

*180°-132°=A*

*48°=A*

*To find C*

*Since C, is subtended by the same arc as A, A could be divided by two, then you'll get 24° for C.*

*To find B. (A+B=diameter(which is always 180°)*

*A+B=180°*

*48°+B=180°*

*B=180°-48°*

*B=132°*

**Today's homework are:**

**-10.3 textbook**

**-read**

**-CYU #2**

**-Practice (odd)**

**-Apply : ALL**

**-Extend 19&21**

**-Workbook, and Extra Practice**

**-journal**

**TEST ON FRIDAY**

*For Tuesday, June 1*

*hand in inside stash-its*

*-problems of the week (#3, and another)*

*-journal*

*-last test signed*

### Scribe May 21

*SCRIBE*Um hello... in class on Friday we learned more things about circles. Chord Properties to be exact. There are four steps to find the interscection of the arcs... Heres a summary of the things we leanred in class recently.

1) You make a chord on the circle.

3)Place compass point on each end of the line. Make arcs above and below the line.

Then heres an example of a question we did, based on the circle we have drawn. We were given that the Chored is 2x and we needed to find the radius of the circle.

Here's how you solve it.

Well... this is it... the homework is 10.2.

### Scribe post for May 11

Ok theres the quick overview of what we did in class. Sorry if I missed some things, I got the main points down I think. Homework was

And today for homework.

### Scribe Post for April 29, 2010

m = slope

y =[mx] + [b] y intercept

slope ^

Slope formula:

y2 - y1 = m

x2 - x1

Ex. (0.1, o.023)

(0.4, 0.092)

y2 - y1 = 0.092 - 0.023

x2 - x1 0.4 - 0.1

= 0.069

0.3

= 0.23

y intercept formula:

y - y1 = m (x-x)

Ex. (0.1, 0.023) (0.4, 0.092)

(x1, y1) (x2, y2)

y - y1 = m (x-x)

y - 0.023 = 0.23 (x-0.1)

y - 0.023 = 0.23x -0.023

y = 0.23x - 0.023 + 0.023

y = 0.23x

HOMEWORK!

Review

The test

Rest of the sheets!

### Scribe Post for April 28, 2010

**purple marbles**as

**red ones.**There are three times as many

**green**as

**purple marbles**. How many green marbles in the bag?

**Red**+

**Purple**+

**Green**= 36

**x + 1/4x + 3(1/4x) = 36**

So there are 18 red marbles. Now you fill in x will 18 to find out how many green marbles there are in the bag.