X(2x+3)-5(x^2-3x)=-3x(2x+2) 2x^2+3x-5x^2+15x=-6x^2-6x 3x^2+24x=0 x^2+8x=0 D=b^2-4ac ( c = 0 ) D= 16 x1,x2 = (-8 +- 4)/2 x1,x2 = -6, -2