11x^2 -6x-9 Step-by-step explanation: 9x^2 - 10x +1 - (-2x^2) + 4x - 10. The opposite of -2x^2 is 2x^2 9x^2 -10x+1+2x ^2 +4x-10 Combine 9x^2 and 2x^2 to get 11x^2 . 11x^2 -10x+1+4x-10 Combine -10x and 4x to get -6X. 11x^2-6x+1-10 Subtract 10 from 1 to get -9. 11x^2 -6x-9
