This is a place for the community of learners in Room 8-73 to learn and enjoy math. It is an extension of the classroom making it accessible 24 hours a day, 7 days a week.

## Tuesday, November 30, 2010

### John Chua's scribe post

DEFINITIONS:

Percent- means it is out of a hundred or another name for hundredths

eg. 65% means 65 out of a 100 or 65/100 or o.65

Fractional percent- a percent that includes a portion of a percent.

eg. 1/2%, 0.42%, 7 3/8%, 125 3/4%, 4.5%

SHOW YOU KNOW:

page 125

A) 248% B)1/4% C)74 8/10%

Page 127

A)

B)

C)

## Thursday, November 18, 2010

### Maya's Text Book Pages

3. Walter walks across a rectangular field in a diagonal line. Maria walks around two sides of the field. They meet at the opposite corner.

7. What is the height of the wheelchair ramp? Give your answer to the nearest tenth of a centimetre.

The answer is 12.6

11. Johan has a 300cm ladder that he leans up against a wall. The safety sticker on the side of the ladder shows that the bottom must be placed between 70 cm and 110 cm away from the wall. What are the minimum distance and maximum distance up the wall that the ladder can reach? Give your answers to the nearest tenth of a centimetre.

The answer is 291.7 cm.

Here are two videos that may help you.

Here's a link to also help you.

### Louis' Homework book: 30 questions 2, 3, 4

**Homework Book Pages 30 questions 2, 3, 4**

**2)**Use the relationship to determine the length of C in each triangle, to the the nearest whole number. Show your work.

b2=c2 - a2

a2=c2 - b2

**3)**Determine the length of each hypotenuse. Show your work.

a2 + b2 = c2

**4) What is the length of each hypotenuse, to the nearest centimeter? Show your work.**

**A)**

### Jennily's Textbook Pages

**Pg 108-110**

**Question 3,9,11**

## Tuesday, November 16, 2010

### Meldrick's Textbook Pages

√a²=√56 mm²

8²+b²=10²

64-64+b²=100-64

Now, imagine that the triangle has been cut in half, from the top right corner to the bottom left corner, so that the diagonal is on a 'flat surface'. Using the height (5mm) and length (12mm), we can find the hypotenuse of the 'triangle' that was created when the rectangle was cut in half, using the Pythagorean theorem (height-a, length-b):

After that, imagine turning the triangle so that you can see the red diagonal cutting a rectangle in half. You have already found the bottom of the rectangle (13mm), and you have the measurements for the right side of the rectangle, the width (7mm). Using the Pythagorean theorem, you can now find the red diagonal (width-a, bottom-b).

Hopefully, you found that helpful. Good night (it's 1:05 AM), and goodbye.

### Textbook Work

I had to do numbers

5, 8, 11, and 14

5)

B)

The area of the square attached to the hypotenuse is 100

C)

The length of the hypotenuse is 10

Here's a link to help you guys!

### Mussie Mesgun Homework Book: Even Questions

24² cm 26² cm=c²

12 = c

b = 10 cm

### Using the Pythagorean Relationship, Homework Book

The

**Pythagorean**relationship can be used to determine the

**Length**of the

**Hypotenuse**of a right triangle when the lengths of the two

**Legs**are known.

3.

**Question**- Determine the length of each hypotenuse. Show your work.

a)

a squared + b squared = c squared

40cm squared + 9cm squared = c squared

(40x40) + (9x9) = c squared

1600cm + 81cm = c squared

The square root of 1681cm = c squared

41 cm squared = c squared

b)

a squared + b squared = c squared

12m squared + 35m squared = c squared

The square root of 1369m squared = c squared

**Question**- Calculate the missing side length for each right triangle, to the nearest tenth of a centimetre. Show your work.

a squared = c squared - b squared

a squared = 6 cm squared - 5 cm squared

a squared = (6x6) - (5x5)

a squared = 36cm squared - 25cm squared

The square root of 11 = a squared

a squared = 3.31cm squared

a squared = 7cm squared - 12cm squared

a squared = (7x7) - (12x12)

a squared = 49cm squared - 144cm squared

The square root of 95 = a squared

a squared = 9.74

7.

**Question**- A triangle is made up of two smaller congruent right triangles.

4.5 = c squared

### Joshua's Pythagoras Scribe Post

9. Tina wants to construct a path along the diagonal of her yard. What length will the path be? Express your answer to the nearest tenth of a metre.

12. The hypotenuse of the triangle cuts the circle in half. What is the diameter of the circle? Express your answer to the nearest tenth of a centimetre.

15. The coordinate grid shown was drawn on centimetre grid paper. What is the line segment of AB? Express your answer to the nearest tenth of a centimetre.

Here is a video to help you:

## Monday, November 15, 2010

### Hazel's Pythagorean Relationship Scribe Post

**Key Ideas**

The Pythagorean relationship can be used to determine the length of the hypotenuse of a right triangle when the lengths of two legs are known.

The Pythagorean relationship can be used to determine the leg length of a right triangle when the lengths of the hypotenuse and the other leg are known.

1. Jack must determine the missing side of a triangle. He decides to draw it and then measure it,as shown. Do you agree with the method that Jack is using? Explain.

Answer: No, I don't agree with the method that Jack is using because it would take too much work. It would be easier if he just used the formula: a²+b²=c² then √c²=c (hypotenuse).

4.What is the length of each hypotenuse? Give your answer to the nearest tenth of a centimetre.

Here is a link to the textbook website.

Here is a link to a pythagoras website.

## Friday, November 12, 2010

### Maya's Text Book Scribe Post

# 10 and 16.

*Estimate*the backdrop side length, to

**one**decimal place.

Answer:

The maximum area of the hot tub is 27m²

The dimensions should be 5.1 by 5.1 so the area does not exceed 75% of the space available.

Here's a video to help you estimate square roots.

## Wednesday, November 10, 2010

### Samarab 8-73 Textbook Post

6) What is an example of a whole number that has a square root between 9 and 10 ?

Answer: 90. 90 is a possible answer .

9) What are the possible whole numbers that has a square root between 4 and 5 ?

Answer : 17,18,19,20,21,22,23,24 . All theses are the possible answers .

### Krizna's Textbook Post

Questions 7 and 8

7.Identify a whole number with a square root between 11 & 12

Answer: the square root of 11 is 111 and the square root of 12 is 144 the square root is 130.

8.Identify all possible whole numbers with a square root between 2 & 3.

Answer:the square root of 2 is 4 & and the square root of 3 is 9. The whole numbers are 5,6,7,8.

### mussie mesgun scribe post

15. order the following numbers from the least to greatest: 7, SQRT 46, 5.8, SQRT 27, 6.3

A) SQRT 27 < 5.8 < 6.3 < SQRT 46 < 7

16. Fitness centre will install a square hot tub in a 6 m x 6 m room. They want the tub to fill no more than 75% of the room's area.

A) What is the maximum area of the hot tub?

Area of a square = LxL

= 6 m x 6 m

= 36 m^2

Area of the hot tub :(75/100)(36) = 27 m^2

B) What dimensions, to a tenth of a meter, will the fitness centre order from the manufacturer?

Explain.

They want the hot tub to fill no more than 75% of the room.

so 75% of the room is : (75/100)(36)= 27 m^2

The dimensions are SQRT 27 = 5.196m

L = 5.1 m

L = 5.1 m

## Tuesday, November 9, 2010

### Maya's Text Book Scribe Post

*Estimate*the backdrop side length, to

**one**decimal place.

Answer:

The maximum area of the hot tub is 27m²

The dimensions should be 5.1 by 5.1 so the area does not exceed 75% of the space available.

Here's a video to help you estimate square roots.

### Square roots

### Ana Lopena's Pythagoras Scribe Post

**12.**While shopping online, Jin Hun finds a square rug with an area of 11m2. He needs to know if it will fit in his 4m x 5m bedroom.

b) Check your estimate with a calculator.

c) Will the rug fit? Explain.

Yes, because the side length of the room is 4m and 5m and the side length of the rug is 3.3m.

**13.** Stella is planning an outdoor wedding. She would like a square dance floor with an area of 115m2.

a) Determine the side length of the nearest tenth of a metre.

b) Stella finds out that the dance floor will be made up of 1m2. What are the two side lengths the dance floor can have that are the closest to what she wants?

**10m x 10m** or **11m x 11m**

c)What are the two square areas for the dance floor that Stella can choose from?

**100m2** or **121m2**

d) Which area will Stella choose? **Explain.**

I think that Stella will choose **121m2** because it is closer to the area that she wanted.