作业帮解下列方程组:a+b+c=-6,a-b+c-8,4a+2b+c=-11(2)3x-y+z=42x+3y-2z=123x+2y=66(3)2x-5y=-117y+4z=55x+2z=2(4)x+y+z=-12x-y-z=1x-2y+z=-4
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解下列方程组:a+b+c=-6,a-b+c-8,4a+2b+c=-11(2)3x-y+z=42x+3y-2z=123x+2y=66(3)2x-5y=-117y+4z=55x+2z=2(4)x+y+z=-12x-y-z=1x-2y+z=-4
解下列方程组:a+b+c=-6,a-b+c-8,4a+2b+c=-11
(2)3x-y+z=4
2x+3y-2z=12
3x+2y=66
(3)2x-5y=-11
7y+4z=5
5x+2z=2
(4)x+y+z=-1
2x-y-z=1
x-2y+z=-4
解下列方程组:a+b+c=-6,a-b+c-8,4a+2b+c=-11(2)3x-y+z=42x+3y-2z=123x+2y=66(3)2x-5y=-117y+4z=55x+2z=2(4)x+y+z=-12x-y-z=1x-2y+z=-4
解下列方程组:
(1).a+b+c=-6.(1)；a-b+c=-8.(2)；4a+2b+c=-11.(3)
(1)+(2)得2(a+c)=-14,故a+c=-7,代入(1)得b=-6+7=1；代入(3)式得4a+c=-13,
即3a+(a+c)=3a-7=-13,故a=-6/3=-2；c=-7-a=-7+2=-5
即a=-2,b=1,-5.
(2).3x-y+z=4.(1)；2x+3y-2z=12.(2)；3x+2y=66.(3)
(1)×2+(2)得8x+y=20,故y=20-8x,代入(3)式得3x+40-16x=66,故x= -26/(13)=-2,y=36,
z=4-3x+y=4+6+36=46.即x=-2,y=36,z=46.
(3).2x-5y=-11.(1)；7y+4z=5.(2)；5x+2z=2.(3)
(2)-2×(3)得 -10x+7y=1.(4)
5×(1)+(4)得-18y=-54,故y=3；代入(1)得x=(1/2)(-11+5y)=(1/2)(-11+15)=2,代入(3)得z=-4.
即x=2,y=3,z=-4.
(4) x+y+z=-1.(1)；2x-y-z=1.(2)；x-2y+z=-4.(3)
(1)+(2)得3x=0,故x=0；代入(1)得y+z=-1.(4)；再将x=0代入(3)得-2y+z=-4.(5)
(4)-(5)得3y=3,故y=1；z=-1-y=-1-1=-2；即x=0,y=1,z=-2.
题写错了吧解下列方程组: (1)a+b+c=-6, a-b+c=-8, 4a+2b+c=-11 (2)3x-y+z=4 2x+3y-2z=12 3x+2y=66由a-b+c=-8可以知道a+c=-8+b 由a+b+c=-6和a+c=-8+b知道b=1, 则a+c=-7 4a+c=-13（把b=1带到式子里)，下面回了吧(2)3x-y+z=4 2x+3y-2z=12 3x+2...
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