Question

In a triangle, the perimeter is $60cm$ and the length of an sides of triangle are $13cm$ and $20cm$. Find the length the third side

Answer 1

Let the length the third side be $x$ cm

As perimeter of triangle$=$Sum of its sides

$\Rightarrow 60=13+20+x$

$\Rightarrow 60=x+33$

$\Rightarrow x=27$cm(third side).