Factor 25y^2-9

$25 y^{2} - 9$

Step 1

Rewrite $25 y^{2}$ as ${(5 y)}^{2}$ .

${(5 y)}^{2} - 9$

Step 2

Rewrite $9$ as $3^{2}$ .

${(5 y)}^{2} - 3^{2}$

Step 3

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = 5 y$ and $b = 3$ .

$(5 y + 3) (5 y - 3)$