当2Y-X=2时,5(x-2y)-3(-x+2y)=
问题描述:
当2Y-X=2时,5(x-2y)-3(-x+2y)=
JIA YOU
答
x=2y-2 原式=5(2y-2-2y)-3(-2y+2+2y) =5×4-3×2 =14
当2Y-X=2时,5(x-2y)-3(-x+2y)=
JIA YOU
x=2y-2 原式=5(2y-2-2y)-3(-2y+2+2y) =5×4-3×2 =14