- 解方程组(初高中衔接)X的平方
- X的平方-3XY+2乘(Y的平方)=0
(2X-Y)的平方-(2X-Y)-30=0
(答案有4个)
- X^2-3XY+2Y^2=0 ------(x-2y)(x-y)=0
------x-2y=0或x-y=0 (1)
(2X-Y)^2-(2X-Y)-30=0 ------(2x-y-6)(2x-y+5)=0
------2x-y-6=0或2x-y+5=0 (2)
联立(1),(2)可得 4 个二元一次方程组
A x-2y=0,2x-y-6=0 解得 x=4 ,y=2
B x-2y=0,2x-y+5=0 解得 x=-10/3 ,y=-5/3
C x-y=0,2x-y+5=0 解得 x=-5 ,y=-5
D x-y=0,2x-y-6=0 解得 x=6 ,y=6