## Algebra 2 (1st Edition)

$21$ inches
Recall: The perimeter $P$ of a rectangle is given by the formula $P=2(l+w)$where $w$=width and $l$=length. The given rectangle has $w=3.5$ inches and $l=7$ inches. Thus, its perimeter is: \begin{align*} P&=2(7+3.5) &\text{inches}\\ P&=2(10.5) &\text{inches}\\ P&=21 &\text{inches} \end{align*}