3x+2Y+Z=315 x+2Y+3z=285

问题描述:

3x+2Y+Z=315 x+2Y+3z=285

3x+2y+z=315
x+2y+3z=285
(3x+2y+z)+(x+2y+3z)=315+285
4*(x+y+z)=600
x+y+z=150元