题目: 直线y=-2x+b经过点P(3,-2 ),则该直线与x轴交点的坐标是______. 答案: 把点P(3,-2 )代入y=-2x+b中,-2×3+b=-2,解得:b=4,则直线解析式为y=-2x+4,当y=0时,-2x+4=0,解得:x=2,则该直线与x轴交点的坐标是(2,0).故答案为:(2,0).
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