如题所述
(1)
②-①:3x+3y=3,得x+y=1 ④
③-①: 24x+6y=60,得4x+y=10 ⑤
⑤-④: 3x=9, 得x=3
代入④:y=1-x=-2
代入①:z=y-x=-5
即解为x=3 , y=-2, z=-5
(2)
①+②+③:4(x+y+z)=-84, 得x+y+z=-21 ④
①-④: x=-5
②-④: y=-9
③-④: z=-7
②-①:3x+3y=3,得x+y=1 ④
③-①: 24x+6y=60,得4x+y=10 ⑤
⑤-④: 3x=9, 得x=3
代入④:y=1-x=-2
代入①:z=y-x=-5
即解为x=3 , y=-2, z=-5
(2)
①+②+③:4(x+y+z)=-84, 得x+y+z=-21 ④
①-④: x=-5
②-④: y=-9
③-④: z=-7
温馨提示:答案为网友推荐,仅供参考