Answer
The side length of the square is $6w+5$.
Work Step by Step
$36w^{2}+60w+25=$
...write first and last terms as squares.
$=(6w)^{2}+60w+(5)^{2}$
...does middle term equal $2ab$?
$60w=2\cdot(6w)\cdot(5)$
$=(6w)^{2}+2\cdot(6w)\cdot(5)+(5)^{2}$
...write as the square of a binomial.
$=(6w+5)^{2}$
The side length of the square is $6w+5$.
