Question

Triangle ABC has perimeter 22cm
AB=8cm
BC=5 cm
By calculation deduce whether triangle ABC is a right-angled triangle

Answer 1

AC = 22 - (8+5) = 22 - 13 = 9

 9^2 + 13^2 = 81 +169 = 250

 22^2 = 484

 So no, ABC is NOT a right triangle because the pythagorean thoerem fails

Hope this helps :)