Question

the formula for the perimeter of a rectangle is $p = 2(l + w)$. solve for $w$.
$w=\frac{p}{2}+l$
$w=\frac{p}{2}-l$
$w = 2p - l$
$w=\frac{p - l}{2}$

Explanation:

Step1: Divide both sides by 2

$\frac{P}{2}=\frac{2(l + w)}{2}$, so $\frac{P}{2}=l + w$.

Step2: Subtract l from both sides

$\frac{P}{2}-l=l + w - l$, so $w=\frac{P}{2}-l$.

Answer:

$w=\frac{P}{2}-l$ (the second option)