Monday, November 15, 2010

Finding Side Lengths

A baseball diamond is a square. How could you determine the distance
from second base to home plate? How many different strategies can
you develop?Determine the length of leg s of the
right triangle

a2+ b2= c2
(27x27) + (27x27) = c2
729m(squared) + 729m(squared)
c21458= c2
1158cm(squared
c238.18m= c


• 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.

a2+b2=c2
3cm+4cm=c2
3x3=9
4x4=16
9+16=25cm
25 square root=5
c=5


• 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.



p2 + q2 = r2
p2 + 122 = 152
p2 + 144 = 225
p2 + 144 - 144 = 225 - 144
p2 = 81
p = √
___
81
p = 9






1. Jack must determine the missing side length 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


I do not agree because, one it would take to long, two when I drew a triangle on grid paper it was very hard to measure the hypotenuse, also its just a lot quicker to use Pythagorean relationships.








2.Kira calculated the missing side length of the right triangle.
y2 = 52+132
y2 = 25
169y2 = 194y2
≈ 13.9
The length of side y is approximately 13.9 cm. Is Kira correct? If she is correct, explain how you know. If she is incorrect,explain the correct method.

Kira is correct because 5x5=25 and 13x13=16
169+25=194
194 square root= 13.9


3. Determine the length of each hypotenuse.


a)
a2+b2=c2
a=12cm 12cm+16cm=c2
b=16cm 12x12=144cm
20cm 16x16=256
144+256=400
400 squared=20


b)
c2-a2=b2
a=16m 30m-16m-c2
b=25.3m 30x30=900
c=30m 16x16=256
900-256=644
644 square root=25.3


4. What is the length of each hypotenuse?
Give your answer to the nearest tenth of
a centimetre.
a)
a=6cm a2+b2=c2
b=7cm 6cm+7cm=c2
c=9.2cm 6x6=36
7x7=49
36+49=85
85 square rooted=9.2

b)
c2-b2=a2
a=7.5cm 11cm-8cm=a2
b=8cm 11x11=121
c=11cm 8x8=64
121-64=57
57 square rooted=7.5




6 comments:

  1. Great post Emily. I like the pictures. It was very big and clear to read. It also looks very organized. Next time add a video and link to make it better. Other than that, great job.

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  2. Your work is very descriptive Emily! You clearly stated your answers and added cool pictures! Next time add a video or two to enhance your work.

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  3. Great post Emily, I liked that you have your work with precise details. I also liked the pictures and the answers were very detailed. I would recommend that you add some colors and try not to leave lots of spaces.

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  4. Great post, Emily! Your answers are organized neatly and it's great that you showed the work for them. The pictures were quite good, too. Next time when you do another scribe, you should add a bit more color to the font for important words, a link and a video so it'll be better. Other than that, good job!

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  5. Good job, Emily! I liked how you showed the work and all your answers were correct. But to make your post more appealing, I'd say to add some color.

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  6. Great job, Emily. I liked how you explained everything on your post and the picture you drew was pretty helpful also. Next time, add a video, link and some color so your post wouldn't be less dull. Other than that, good job.

    ReplyDelete