解方程组 3/5x-30=y 3/4(x-10)=y+10

问题描述:

解方程组 3/5x-30=y 3/4(x-10)=y+10
跪求,快啊 急需

3/5x-30=y
3/4(x-10)=y+10
3x-5y=150
3x-4y=70
-4y-(-5y)=70-150
y=-80
x=(70+4y)/3=[70+4×(-8-250/30]/3=-250/3