Question

The perimeter of a rectangle is $20$ units. If the length of any one of the sides is $6$ units, the length of the other side is .

• A. $4$ units
• B. $6$ units
• C. $8$ units

Answer 1

The correct option is A $4$ units

Let the length of the unknown side be $s$ units.
Since, we know that the perimeter of a rectangle $=2\times ({\text{side}}_1+{\text{side}}_2)$
$\Rightarrow 20=2\ast (6+s)$
$\Rightarrow 20=12+2s$
Subtracting $12$ from both sides:
$\Rightarrow 20-12=12+2s-12$
$\Rightarrow 2s=8$
Now, dividing with $2$ on both sides:
$\Rightarrow \frac{2s}{2}=\frac{8}{2}$
$\Rightarrow s=4$ units.