Question

A piece of string is $30\text{cm}$ long. What will be the length of each side if the string is used to form a square?

Answer 1

Step 1: Let the side of the square be $s$. The perimeter, $P$ of the square is, $P=4s$. Substitute $P=30$ into the formula of perimeter and solve for $s$.

$\begin{array}{rcl}P& =& 4s\\ 30& =& 4s\end{array}$

Step 2: Divide both sides of the equation by $4$ and solve for $s$.

$\begin{array}{rcl}\frac{30}{4}& =& \frac{4s}{4}\\ 7.5\text{cm}& =& s\end{array}$

Hence, the side of the square is, $7.5\text{cm}$.