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> 若3x+2y+4z=4,x﹣y+z=2,求x+4y+2z的值.-七年级数学
若3x+2y+4z=4,x﹣y+z=2,求x+4y+2z的值.-七年级数学
题目简介
若3x+2y+4z=4,x﹣y+z=2,求x+4y+2z的值.-七年级数学
题目详情
若3x+2y+4z=4,x﹣y+z=2,求x+4y+2z的值.
题型:计算题
难度:中档
来源:浙江省竞赛题
答案
解:由x﹣y+z=2得,2x﹣2y+2z=4,
∴
,
∴由②﹣①得,x+4y+2z=0,
所以,x+4y+2z的值为0.
上一篇 :
若,且3x-2y+5z=-20,则x+3y-z=()。-
下一篇 :
在关于x1,x2,x3的方程组中.已知a
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题目简介
若3x+2y+4z=4,x﹣y+z=2,求x+4y+2z的值.-七年级数学
题目详情
答案
∴
∴由②﹣①得,x+4y+2z=0,
所以,x+4y+2z的值为0.