-3x+47=8
3x=47-8
3x=39
x=13
x+2y+6=0
13+2y+6=0
2y=-19
y=-9.5 卧槽。我发现我题目发错了。。。-3x+4y=8x+2y+6=0x+2y+6=03x+6y+18=06y+18=-3x 6y+18+4y=810y=-10y=-1 x-2x1+6=0x+4=0x=-4