Question

Triangle ABC has perimeter 22 cm.

AB = 8cm
BC = 5cm
By calculation, deduce whether triangle ABC is a right-angled triangle.

Answer 1

Explanation:

A = 8 cm

B = 5 cm

C = 22 - 8 - 5 = 9 cm

Use the Pythagreom Theroem (a^2 + b^2 = c^2) if the two sides are equal to one another than it is a right triangle.

8^2 + 5^2 = 9^2

64 + 25 = 81

89 = 81

89 does not equal 81, so this is not a right triangle.