Respuesta :

musiclover10045

(10х — 4х2) - (7х + ?) = 3х – 6х2

10x - 7x = 3x which is given,

Now you have -4x^2 - ? needs to equal -6x^2

write it as an equation:

-4x^2 - ? = -6x^2

To solve for ? add 4x^2 to each side:

-? = -2x^2

Multiply each side by -1:

? = 2x^2