(5x-7)(8x+1)=(8x+1)²
40x²-56x+5x-7=64x²+16x+1
40x²-51x-7=64x²+16x+1
40x²-51x-7-64x²-16x-1=0
-24x²-67x-8=0
24x²+67x+8=0
24x²+64x+3x+8=0
8x(3x+8)+3x+8=0
(3x+8)(8x+1)=0
x1=-8/3, x2=-1/8
x1=-2 2/8, x2=-1/8
(5x-7)(8x+1)=(8x+1)²
40x²-56x+5x-7=64x²+16x+1
40x²-51x-7=64x²+16x+1
40x²-51x-7-64x²-16x-1=0
-24x²-67x-8=0
24x²+67x+8=0
24x²+64x+3x+8=0
8x(3x+8)+3x+8=0
(3x+8)(8x+1)=0
x1=-8/3, x2=-1/8
x1=-2 2/8, x2=-1/8