Question

A triangle has the side lengths of 28 in,4in and31 inches. classify it as acute, obtuse or right

Answer 1

The answer is obtuse

a = 4
b = 28
c = 31

If a² + b² > c²    -  the angle is acute
If a² + b² < c²    -  the angle is obtuse
If a² + b² = c²    -  the angle is right

a² + b² = 4² + 28² = 16 + 784 = 800
c² = 31² = 961

    800 < 900
a² + b² < c²  

Therefore, the angle is obtuse