# A rectangle has a width that is twice as long as its lengths and an area of 722 square inches, how do you find the length of the diagonal?

Aug 30, 2017

See below.

#### Explanation:

If $x$ is the length then the width is $2 x$.
Area is $x$ x $2 x$ = $2 {x}^{2}$ = $722 \implies$x = $\sqrt{\frac{722}{2}}$$\implies x = 19$
Length is 19, width is 38.

By Pythagoras theorem:

Diagonal is $\sqrt{{19}^{2} + {38}^{2}} = 42.49$ $\textcolor{b l u e}{2. d . p .}$