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“ab=4”是“直线2x+ay-1=0与直线bx+2y-2=0平行”的( ) A...
“ab=4”是“直线2x+ay-1=0与直线bx+2y-2=0平行”的( )
A.充分必要条件
B.充分而不必要条件
C.必要而不充分条件
D.既不充分也不必要条件
考点分析:
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