Question

The perimeter of an isosceles triangle is 21 cm. Find the measure of equal sides given that the third side is 5 cm.

Answer 1

Perimeter of the triangle P = (a + b + c) units.

21 = [(a + b) + 5] cm

21 – 5 = a + b

16 = a + b

Here a and b are equal sides and let a = b

16 = a + a

2a = 16

a = 16/2

a = 8 cm.

∴ Equal sides measure 8 cm.