2x-y-3=3
3x+2y-8=0
4x-2y=12
3x+2y=8
7x=20
x=20/7
40/7-y-3=3
y=6-40/7
y=2/7
不懂可追问,有帮助请采纳,谢谢!
2x-y=6①
3x+2y=8②
①*2+②
4x-2y+3x+2y=12+8
7x=20
x=20/7
y=40/7-6
y=2/7
先移向 2x-y=3+3 ,2x-y=6 ,3x+2y=8
然后大括号{2x-y=6为1式,3x+2y=8为2式,将1式乘以2则为4x-2y=12,然后式1+式2,7x=20,x=20/7,将x=20/7代入式一,2×20/7-y=6,-y=6-40/7,-y=42/7-40/7,-y=2/7,y=-2/7