Answer
The length is 17 m and the width is 12 m.
Work Step by Step
Let the width be $x$. Then, the length will be $x+5$. Now the perimeter is
$$2x+2(x+5)=58\Longrightarrow 4x+10=58$$
that is, $4x=48$ and hence $x=12$. Thus, the length is 17 m and the width is 12 m.
