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Math Challenge I-C Handout 3 assignment

 
 
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Math Challenge I-C Handout 3 assignment
by Christina Peng - Saturday, 16 December 2017, 1:22 PM
 

Hello, can someone please help me with these questions? -_-' Thanksssss

3.22

In this question, is ADE equilateral? 

would the equation 3y=12 , y=4 be right for the side length of ADE? 

3.23

What does "opposite sides" mean?

3.24

I don't know how to do this.

3.25

I don't know how to do this.

3.30

I don't know how to do this.

 
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Re: Math Challenge I-C Handout 3 assignment
by David Reynoso - Monday, 18 December 2017, 10:19 AM
 

  • 3.22: The problem is telling us that the sides $DE$ and $BC$ of triangles $ADE$ and $ABC$ are parallel. Based on that, what can we say about the angles of triangle $ADE$ and $ABC$? Could you use that to show that $ADE$ is also an equilateral triangle?
  • 3.23: You want to show that two angles in a triangle are equal if and only if the sides that are opposite to those two angles are equal.


What have you tried so far for 3.24, 3.25 and 3.30? Here are some hints:

  • 3.24: try looking for some similar or congruent triangles.
  • 3.25 and 3.30: remember the ratio of the sides of $45-45-90$ triangles is $1:1:\sqrt{2}$, and the ratio of the sides of $30-60-90$ triangles is $1:\sqrt{3}:2$. 
Picture of Christina Peng
Re: Math Challenge I-C Handout 3 assignment
by Christina Peng - Tuesday, 19 December 2017, 9:57 PM
 

Thank you!