2x-3y-2=0 (2x-3y+5) / 7+2y=9 x= y=

2x-3y-2=0 (2x-3y+5) / 7+2y=9 x= y=

2x-3y = 2
대입
7/7+2y=9x
1+2y=9x
즉 2x-3y=2
9x-2y=1
해득 x = 7/31
y=-16/31