Answer
x = $\sqrt 37 w$
Work Step by Step
Since the triangle is a right angle triangle we use the pythagorean theorem.
$a^{2} + b^{2} = c^{2}$
In this problem a=6w, b=w and c= x
$(6w)^{2} + (w)^{2} = x^{2}$
$ 6w \times 6w + (w)^{2} = x^{2}$
$36w^{2} + w^{2} = x^{2}$
$37w^{2} = x^{2}$
We take square root of both sides
$\sqrt (37w^{2}) = \sqrt x^{2}$
$\sqrt 37 w$ = x
Therefore x = $\sqrt 37 w$