问题标题:
4x-9z=173x+y+15z=18x+2y+3z=2x+y+z=26x-y=12x+z-y=18
问题描述:

4x-9z=173x+y+15z=18x+2y+3z=2

x+y+z=26x-y=12x+z-y=18

党华锐回答:
  4x-9z=17(1)   3x+y+15z=18(2)   x+2y+3z=2(3)   (2)*2得:6x+2y+30z=36(4)   (4)-(3)得:5x+27z=34(5)   (1)*3得:12x-27z=51(6)   (5)+(6)得:.17x=85,x=5   将x=5带入(1)得z=1/3   将x=5.z=1/3带入(2)得:y=-2   所以x=5.y=-2.z=1/3   2)x+y+z=26(1)   x-y=1(2)   2x+z-y=18(3)   (3)-(1)得:x-2y=-8(4)   (2)-(4)得:y=9   将y=9带入(2)得:x=10   将x=10,y=9带入(1)得z=7   所以x=10,y=9,z=7
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