Solve for y a=9y+3yx

$a = 9 y + 3 y x$

Rewrite the equation as $9 y + 3 y x = a$ .

$9 y + 3 y x = a$

Factor $3 y$ out of $9 y + 3 y x$ .

Factor $3 y$ out of $9 y$ .

$3 y (3) + 3 y x = a$

Factor $3 y$ out of $3 y x$ .

$3 y (3) + 3 y (x) = a$

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

$3 y (3 + x) = a$

Divide each term in $3 y (3 + x) = a$ by $3 (3 + x)$ and simplify.

Divide each term in $3 y (3 + x) = a$ by $3 (3 + x)$ .

$\frac{3 y (3 + x)}{3 (3 + x)} = \frac{a}{3 (3 + x)}$

Simplify the left side.

Cancel the common factor of $3$ .

Cancel the common factor.

$\frac{3 y (3 + x)}{3 (3 + x)} = \frac{a}{3 (3 + x)}$

Rewrite the expression.

$\frac{y (3 + x)}{3 + x} = \frac{a}{3 (3 + x)}$

Cancel the common factor of $3 + x$ .

Cancel the common factor.

$\frac{y (3 + x)}{3 + x} = \frac{a}{3 (3 + x)}$

Divide $y$ by $1$ .

$y = \frac{a}{3 (3 + x)}$