The lengths of three sides of a triangle are given. determine whether each triangle is a right triangle.
1. 14 m, 5 m, 4 m

2. 3 in., 4 in., 5 in. are these right triangles?

In a right triangle, the hypotenuse is always the longest side.  Plus, the hypotenuse squared has to equal the sum of the squares of the other 2 sides.  For the first "triangle" above: does ?  Let's check.  196 = 25 + 16 so does 196 = 41?  Obviously not.  So that is not a right triangle.  Let's check the second one the same way.  Does ?  25 = 9 + 16.  Does 25 = 25?  Of course it does!  So 1 is not a right triangle, but 2 is!