Question 175864
To tell whether a triangle is a right triangle, you need the measurements it gives you first; 

Here's an example:

The three sides of a triangle are 14, 19, 23. Prove if it's a 
right triangle.

Pythagorean Theorem: a^2 + b^2 = c^2. The largest measurement is always the Hypotenuse.

14^2 + 19^2 = 23^2
196 + 361 = 529 Add the sides A and B.
557 = 529 Is this right? No. So, the triangle is NOT a right triangle.

If the triangle WAS right, then the numbers would equal each other.