(3x-1)(2x+6)-(2x-2)(3x+1)= -24
6x^2+18x-2x-6-6x^2-2x+6x+2+24=0
20x+20=0
x= -1
(3x+9)(x-5)-(x-7)(3x-1)=12+8x
3x^2-15x+9x-45-3x^2+x+21x-7-12-8x=0
8x-64=0
x=8
(3x-1)(2x+6)-(2x-2)(3x+1)= -24
6x^2+18x-2x-6-6x^2-2x+6x+2+24=0
20x+20=0
x= -1
(3x+9)(x-5)-(x-7)(3x-1)=12+8x
3x^2-15x+9x-45-3x^2+x+21x-7-12-8x=0
8x-64=0
x=8