tolong ya teman-teman besok mau dikumpul please please please please makasih

1. x²+7x-3x-21 = x²+4x-21
2.x²-2x+4x-8 = x²+2x-8
3.6x²+2x+21x+7 = 6x²+23x+7
4.x²+4x-4x-16 = x²-16
5.4x²-6x+6x-9 = 4x²-9
6.9x²+3x-3x-1 = 9x²-1
7.(2x+7)(x+1)
8(4x-1)(2x-3)
9.(3x+2)(x-3)
10.(4x+7)(4x-7)