Question

Two sides of a triangle are $15cm$ and $20cm.$ The perimeter of the triangle is $50cm.$ What is the third side?

Answer 1

Given:
Perimeter $=50cm$

Length of the first side $=15cm$

Length of the second side $=20cm$

We have to find the length of the third side.

The perimeter of a triangle $=$ Sum of all three sides of the triangle

$\therefore$ Length of the third side $=$ (Perimeter of the triangle) $-$ (Sum of the length of the other two sides)

$=50-(15+20)$

$=50-35=15cm$