Question

How do you combine like terms in `(- 8y ^ { 2} + 4y - 1) + ( 9y ^ { 2} + 3y - 1) - ( - 9y ^ { 2} + 3y - 8)`?

Answer 1

`2(5y^2+2y+3)`

Explanation:

`(-8y^2+4y-1)+(9y^2+3y-1)-(-9y^2+3y-8)`

`=-8y^2+4y-1+9y^2+3y-1color(red)(+9y^2-3y+8)`

`=-8y^2+9y^2+9y^2+4y+3y-3y+6`

`=10y^2+4y+6`

`=2(5y^2+2y+3)`