(9x-4)²-(x-20)²=0
81х²-72х+16-х²+40х-400=0
80x²-32x-384=0
16(x+2)(5x-12)=0
(x+2)(5x-12)=0
x+2=0 5x-12=0
x1=-2 5x=12
x2=12/5
(9x-4)²-(x-20)²=0
81х²-72х+16-х²+40х-400=0
80x²-32x-384=0
16(x+2)(5x-12)=0
(x+2)(5x-12)=0
x+2=0 5x-12=0
x1=-2 5x=12
x2=12/5