Simplify (k^2-y^2)/(3k+3y)

$\frac{k^{2} - y^{2}}{3 k + 3 y}$

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

$\frac{(k + y) (k - y)}{3 k + 3 y}$

Simplify terms.

Factor $3$ out of $3 k + 3 y$ .

Factor $3$ out of $3 k$ .

$\frac{(k + y) (k - y)}{3 (k) + 3 y}$

Factor $3$ out of $3 y$ .

$\frac{(k + y) (k - y)}{3 (k) + 3 (y)}$

Factor $3$ out of $3 (k) + 3 (y)$ .

$\frac{(k + y) (k - y)}{3 (k + y)}$

Cancel the common factor of $k + y$ .

Cancel the common factor.

$\frac{(k + y) (k - y)}{3 (k + y)}$

Rewrite the expression.

$\frac{k - y}{3}$