Tuesday, November 30, 2010
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:
A) 248% B)1/4% C)74 8/10%
Thursday, November 18, 2010
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.
b2=c2 - a2
a2=c2 - b2
a2 + b2 = c2
Tuesday, November 16, 2010
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.
I had to do numbers
5, 8, 11, and 14
The area of the square attached to the hypotenuse is 100
The length of the hypotenuse is 10
Here's a link to help you guys!
24² cm 26² cm=c²
12 = c
b = 10 cm
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 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
a squared + b squared = c squared
12m squared + 35m squared = c squared
The square root of 1369m squared = c squared
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
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
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
# 10 and 16.
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
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 .
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.
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?
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
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.