Question

what should be added to x (x-3)+7 to get 2x (2-x) -9?​

Answer 1

Answer:

$-3x^2 + 7x - 16$ is to be added to x (x-3)+7 to get 2x (2-x) -9.

Step-by-step explanation:

If A is added to x (x-3)+7 to get 2x (2-x) -9

A + ​x (x-3)+7 = 2x (2-x) -9

$A + x^2 - 3x + 7 = 4x - 2x^2 - 9$

Rearrange the terms

$A = 4x - 2x^2 - 9 - x^2 + 3x - 7\\A = 4x + 3x - 2x^2 - x^2- 9- 7\\A = 7x - 3x^2 - 16$