Pre-Algebra Examples

$(9 r^{3} + 5 r^{2} + 11 r) + (- 2 r^{3} + 9 r - 8 r^{2})$

Step 1

Remove parentheses.

$9 r^{3} + 5 r^{2} + 11 r - 2 r^{3} + 9 r - 8 r^{2}$

Step 2

Subtract $2 r^{3}$ from $9 r^{3}$ .

$7 r^{3} + 5 r^{2} + 11 r + 9 r - 8 r^{2}$

Step 3

Subtract $8 r^{2}$ from $5 r^{2}$ .

$7 r^{3} - 3 r^{2} + 11 r + 9 r$

Step 4

Add $11 r$ and $9 r$ .

$7 r^{3} - 3 r^{2} + 20 r$