Solve for r -1=-3(3r-8)-7

$- 1 = - 3 (3 r - 8) - 7$

Step 1

Rewrite the equation as $- 3 (3 r - 8) - 7 = - 1$ .

$- 3 (3 r - 8) - 7 = - 1$

Step 2

Simplify $- 3 (3 r - 8) - 7$ .

Simplify each term.

Apply the distributive property.

$- 3 (3 r) - 3 \cdot - 8 - 7 = - 1$

Multiply $3$ by $- 3$ .

$- 9 r - 3 \cdot - 8 - 7 = - 1$

Multiply $- 3$ by $- 8$ .

$- 9 r + 24 - 7 = - 1$

Subtract $7$ from $24$ .

$- 9 r + 17 = - 1$

Step 3

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

Subtract $17$ from both sides of the equation.

$- 9 r = - 1 - 17$

Subtract $17$ from $- 1$ .

$- 9 r = - 18$

Step 4

Divide each term in $- 9 r = - 18$ by $- 9$ and simplify.

Divide each term in $- 9 r = - 18$ by $- 9$ .

$\frac{- 9 r}{- 9} = \frac{- 18}{- 9}$

Simplify the left side.

Cancel the common factor of $- 9$ .

Cancel the common factor.

$\frac{- 9 r}{- 9} = \frac{- 18}{- 9}$

Divide $r$ by $1$ .

$r = \frac{- 18}{- 9}$

Simplify the right side.

Divide $- 18$ by $- 9$ .

$r = 2$