(1)x²-6x=6
x²-6x+9=6+9
(x-3)²=15
x-3=±√15
x1=3+√15 x2=3-√15
(2)x²-2x=1
x²-2x+1=1+1
(x-1)²=2
x-1=±√2
x1=1+√2 x2=1-√2
(3)x²+8x=16
x²+8x+16=16+16
(x+4)²=32
x+4=±4√2
x1=-4+4√2 x2=-4-4√2