X+Y+Z=50 (1) 3X+2Y+0.5Z=100 (2) (1)X3-(2) 3x+3Y+3Z=150 3X+2Y+0.5Z=100 Y+2.5Z=50 Y=50-2.5Z Z=10 Y=25 (2)-(1)X2 2X+2Y+2Z=100 X-1.5Z=0 X=1.5Z X=15
求采纳
解:X+Y+Z=50 (1)
3X+2Y+0.5Z=100 (2)
(2)-(1)×2得 x-1.5z=0 带入(1)(2)得
∴Y+2.5Z=50 (3)
2Y+ 5Z=100 (4)
∴ z=2 x=3 y=45
z=4 x=6 y=40
z=6 x=9 y=35
z=8 x=12 y=20
z=10 x=15 y=25
z=12 x=18 y=20
z=14 x=21 y=15
z=16 x=24 y=10
z=18 x=27 y=5
z=20 x=30 y=0
z=22 x=33 y=-5
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