当a=______时,方程组x+2y-6=0,且x-y-9+3a=0的解满足x=y.
问题描述:
当a=______时,方程组x+2y-6=0,且x-y-9+3a=0的解满足x=y.
答
把x=y 带入原式,可得a=3.或者两个方程合并化简得y=a-1,x=8-2a,若x=y,也可得a=3
当a=______时,方程组x+2y-6=0,且x-y-9+3a=0的解满足x=y.
把x=y 带入原式,可得a=3.或者两个方程合并化简得y=a-1,x=8-2a,若x=y,也可得a=3