x的平方-4xy+4y的平方=1(x-2y)²=1x-2y=1 或x-2y=-1x=2y+1 或x=2y-1x的平方-5xy-6y的平方=0(x-6y)(x+y)=0x-6y=0 或x+y=0x=2y+1 时2y+1-6y=0 y=1/4 x=3/22y+1+y=0 y=-1/3 x=1/3x=2y-1时2y-1+6y=0 y=1/8 x=-3/42y-...