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已知直线l1:y=-x+2a与直线平行,则a的值为( ) A. B.±1 C.1...
已知直线l
1:y=-x+2a与直线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101230919273840390/SYS201311012309192738403007_ST/0.png)
平行,则a的值为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101230919273840390/SYS201311012309192738403007_ST/1.png)
B.±1
C.1
D.-1
考点分析:
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