Question

How do you simplify `(4x^2 + 15x - 18) - (9x^2 - 5x + 19) - (-5x^2 + 18x - 20) - (-4x^2 - 7x + 15)`?

Answer 1

`=color(red)(4x^2 ) + color(blue)(9x) -32`

Explanation:

`4x^2 + 15x - 18- 9x^2 + 5x -19 +5x^2 - 18x +20 +4x^2 +7x -15`

Grouping like terms:
`color(red)((4x^2 -9x^2+5x^2 +4x^2 ) ) + color(blue)((15x+5x-18x+7x)) + (-18 -19+20 -15)`

`=color(red)(4x^2 ) +color(blue)(9x) -32`