x/4+y/3=3/4
两边同时乘以4,则
x+4y/3=3
x=3-4y/3
5(x-9)=6(y-2)
则 5x-45=6y-12
x=6y/5+33/5
3-4y/3=6y/5+33/5
45-20y=18y+99
y=54/38
x=