问题:
已知方程( ) 2-5( )+6=0,设 =y,则原方程可变形为
[ ]
A.y 2+5y+6=0
B.y 2-5y+6=0
C.y 2+5y-6=0
D.y 2-5y-6=0
已知方程( ) 2-5( )+6=0,设 =y,则原方程可变形为
B.y 2-5y+6=0
C.y 2+5y-6=0
D.y 2-5y-6=0
[ ]
A.y 2+5y+6=0 B.y 2-5y+6=0
C.y 2+5y-6=0
D.y 2-5y-6=0
参考答案: