Solve for f -18f+20=-20-15f-20

$- 18 f + 20 = - 20 - 15 f - 20$

Subtract $20$ from $- 20$ .

$- 18 f + 20 = - 15 f - 40$

Move all terms containing $f$ to the left side of the equation.

Add $15 f$ to both sides of the equation.

$- 18 f + 20 + 15 f = - 40$

Add $- 18 f$ and $15 f$ .

$- 3 f + 20 = - 40$

Move all terms not containing $f$ to the right side of the equation.

Subtract $20$ from both sides of the equation.

$- 3 f = - 40 - 20$

Subtract $20$ from $- 40$ .

$- 3 f = - 60$

Divide each term in $- 3 f = - 60$ by $- 3$ and simplify.

Divide each term in $- 3 f = - 60$ by $- 3$ .

$\frac{- 3 f}{- 3} = \frac{- 60}{- 3}$

Simplify the left side.

Cancel the common factor of $- 3$ .

Cancel the common factor.

$\frac{- 3 f}{- 3} = \frac{- 60}{- 3}$

Divide $f$ by $1$ .

$f = \frac{- 60}{- 3}$

Simplify the right side.

Divide $- 60$ by $- 3$ .

$f = 20$