SOLUTION: If triangle ABC is a triangle such that a^2 + b^2 = c^2, then angle BCA is a right triangle?  This is the converse to the Pythagorean Theorem. Please do not use law of cosine!
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Question 192713This question is from textbook 
:  If triangle ABC is a triangle such that a^2 + b^2 = c^2, then angle BCA is a right triangle?  This is the converse to the Pythagorean Theorem. Please do not use law of cosine! 
This question is from textbook 
Answer by jojo14344(1513)   (Show Source): You can put this solution on YOUR website!
 
If triangle ABC has dimensions , we want to prove angle BCA is a Right Triangle.
Remember a Square is formed by four Right Triangles, being each triangle has the same dimensions as the other triangles.
See figure below:
We get the Area of the outer Square:
Also,
*Note:  ----> Area of 4 Right Triangles outside the inner square.
Therefore,
Then, Triangle ABC has sides 
 ---> Angle BCA is Right Triangle
Thank you,
Jojo
 
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