ABC is a triangle in which BC = 10 cm, CA = 6 cm and AB = 8 cm (BC)2=(10)2=100 (CA)2=(6)2=36 (AB)2=(8)2=64 Consider, (CA)2+(AB)2 ⇒36+64 ⇒100 ⇒(BC)2 Here, the square of the hypotenuse side is equal to the sum of squares of the other two sides“ Pythagorean theorem is true. ⇒ ABC is a right-angled triangle.