(x+4)(4x-3)=x^2+5x+4 4x^2-3x+16x-12-x^2-5x-4=0 3x^2+8x-16=0 D=8^2+16*4*4=256=16^2 x1=(-8+16)(2*3)=8/6=4/3=1 целая 1/3 x2=(-8-16)(2*3)=-24/6=-4