Question

what should be subtracted from 1+x-x^2 to get 2x+x^2​

Answer 1

Let the quantity to be subtracted be y.

$1 + x - {x}^{2} - y = 2x + {x}^{2}$

$- y = 2 {x}^{2} + x - 1$

$y = 1 - x - 2 {x}^{2}$

Answer 2

Answer:

(1-x-2x^2) should be subtracted from (1+x-x^2) to get (2x+x^2)