(2x+7)(x^2+12x-30)-5x^2=2x^2(x+1)
(2x+7)(x+15)(x-2)=5x^2+2x^3+2x^2
(2x+7)(x+15)(x-2)=(2x+7)x^2
(x+15)(x-2)=x^2
12x = 30
x =2,5
(2x+7)(x^2+12x-30)-5x^2=2x^2(x+1)
(2x+7)(x+15)(x-2)=5x^2+2x^3+2x^2
(2x+7)(x+15)(x-2)=(2x+7)x^2
(x+15)(x-2)=x^2
12x = 30
x =2,5