(①+②+③)/备扮4:橡桐 x+y+z=6 ④①-④:仿如灶 x=-2②-④: y=2③-④: z=6所以:x=-2,y=2,z=6
2x+y+z=4x+2y+z=8x+y+2z=124x+4y+4z=4+8+12=24x+y+z=24/搜轿厅世隐帆答4=6x=4-6=-2y=8-6=2z=12-6=6
x= 4 y=4 z=-8