只要保证
y1=y2使得
x²+2x-8=0即可
(1)y=0
x²+2x-8=0,对
(2)
y1=y2
x²=-2x+8
x²+2x-8=0,对
(3)
y1=y2
x²+2x=9
x²+2x-8=0,对
(4)
y1=y2
x²-8=-2x
x²+2x-8=0,对
正确有4个,都对
只要保证
y1=y2使得
x²+2x-8=0即可
(1)y=0
x²+2x-8=0,对
(2)
y1=y2
x²=-2x+8
x²+2x-8=0,对
(3)
y1=y2
x²+2x=9
x²+2x-8=0,对
(4)
y1=y2
x²-8=-2x
x²+2x-8=0,对
正确有4个,都对