#### Answer

$y = -\frac{5}{2}~~$ or $~~y = \frac{5}{2}$

#### Work Step by Step

The general form of factoring the difference of two squares is as follows:
$x^2-y^2 = (x+y)~(x-y)$
We can rearrange and solve the given equation as follows:
$4y^2 = 25$
$4y^2 - 25 = 0$
$(2y+5)~(2y-5) = 0$
$2y+5 = 0~~$ or $~~2y-5 = 0$
$y = -\frac{5}{2}~~$ or $~~y = \frac{5}{2}$