已知|2x-y-3|+(2x+y+11)²=0,则有( )A、x=-2,y=-7B、x=-1,y=-5C、x=0,y=-3D、x=2,y=1
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已知|2x-y-3|+(2x+y+11)²=0,则有( )A、x=-2,y=-7B、x=-1,y=-5C、x=0,y=-3D、x=2,y=1
已知|2x-y-3|+(2x+y+11)²=0,则有( )
A、x=-2,y=-7
B、x=-1,y=-5
C、x=0,y=-3
D、x=2,y=1
已知|2x-y-3|+(2x+y+11)²=0,则有( )A、x=-2,y=-7B、x=-1,y=-5C、x=0,y=-3D、x=2,y=1
选A.
2X-Y-3=0,2X+Y+11=0
=>
Y=2X-3代入2X+Y+11=0中,
=>4X-3=-11,X=-2,Y=-7.
故选A.
2x-y-3=0 2x+y+11=0
两式相减得:2y=-14 y=-7 x=-2 选A
A 如果你不会的话可以一一带入嘛^-^毕竟这是选择题不用过程的(哈哈,比较麻烦但很实用)
2x-y-3=0 2x+y+11=0
2x-y=3 2x+y=-11
x=-2,y=-7
|2x-y-3|+(2x+y+11)²=0
因为|2x-y-3|≥0;(2x+y+11)²≥0
所以|2x-y-3|=0;(2x+y+11)²=0
2x-y-3=0
2x+y+11=0
x=-2,y=-7
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