Answer:
x²+4x-12
Explanation:
The first step is the multiplication in the last part of polinomial
(2x+4)(3x-7)
We multiply first with first, first with second then second with first and second with second
6x²-14x+12x-28
=6x²-2x-28
The complete polynomial
3x²+9x+6-8x²-3x+10+6x²-2x-28
Then we goup the grades
3x²-8x²+6x²=x²
9x-3x-2x=4x
6+10-28=-12
All this in the polynomial form
x²+4x-12