Question

Given is an isosceles triangle ABC. The length of one of its sides is represented by $s$. The other two sides are of equal length. Their length is two times the length of the side represented by $s$. Express the perimeter of the triangle in terms of $s$.

Answer 1

An isosceles triangle ABC with one of its side $s$ is shown in the figure and the other two sides of the triangle are of equal length.

According to the question, Two sides of equal length are two times the length of the side represented by $s$, i.e, the other two sides are each represented by $2s$.

We know that :

Perimeter is equal to the sum of all sides of the triangle, i.e , P $$\begin{gathered} =2s+s+2s \\ =5s \end{gathered}$$

Hence, the perimeter of the triangle is equal to $5s$.