三元一次方程组计算专项练习题(有答案).docx

三元一次方程组计算专项练习题(有答案).docx三元一次方程组专项练****2x+3y4-z=6r2x+3y-z二4VX--y+2z=-1<3x-2y+3z二7x+2y-z二5 ox+3y-2z二_1•\+y+z=12x+y_z=5<x+2y-z二6 <2x+3y4-z=103x■-y+-z二20■2a+b+c-0c+2y_z二6《4a+2b+c-5 <:?x+y+z二92a—b+c=:?x+4y+z=18."3x-y+z-4I-c=3x+y+z=6«a一2b二-92x+3y-z=12gt2c+a-47・.x+y+z二6 >3x-y+2z=3x+y+z=6<X-•尸12x4y-3z=ll«x+y-z=02x■-。]x+y+z=12x"y=-1‘3x+2y+5z二2/X_y+z二2<X-2y-z二6Vx+y-z=-24x+2y~7z=30.・+y4-z=0 ."x+y=-2"x+y=2z二4<y+z二-1<X-2y+z二-+x二3 .+2y+3z=0.•3x44z=7①x+y+z=12J2x+3y+z二9②€K+2y-z二6匹:X-9y+7z=8③・:3x_y+z二10••x+y+z二4 ①x-y+z=O②X_乙二8 ③x+y+z=l"3x+2y+z二13<x-2y~z二3<x+y+2z=72x-y+z二0b •+3y-z=12I •X-・y+2z二5①|Xy:z—7:8:9•2x+y-z=l②(2x+7y_6z=16■-z-0 ③-y-5z二4<2x+y-3z=1023・[3x+y+z=8.(7x+3y=・6y二10成立,求m的值・、,(x-2y=-2a方程组(力+5尸n+6的解x、-2y+z=-52x+y_3z=103x+2y-+y=2y+2z=4x+-y+z二42x+3y-z=12x+y+z二61)x+y+z二26x=y+l2x-y+z=18xyz■ ■II 2一3一4卫+y++y+z二2<x-2y+z=-1(2)[x+2沪3z二--z二4x-y+z=lk2x+3y+2z=-y=8x+y+z=32x-y+.'3x-y+z二42x+3y-z=+y+z二6 .+y+z=5x+2y+z二3ix+y+2z二42x-y+z二33x+4y-z=8x+y一2z二一338在y=ax2+bx+c中,当x=0时,y=-7;x=l时y=-9;x=-1时,y二・3,求8、b、-b+c二0*4宫+2b+c二339.、90_3b++y-2z二0<llx+4y-8z=740.[27x+104y-54z=77x+y+z二4<2x-y+z二34]. -x+2y-z=-1x+y+z二6•4x+2y+z=ll42.【9x+3y+z二18.<5x+4y+z二03x+y-4z=ll43・x+y+z二-23x-y+2z二3<2x+y-z二1344.[x+2y+z二20.<3x一y+2z=32x+y-3z=ll <'x+y_z二6x-3y++y+z二12 .+2y一z二3"x+2y+3z二11r2x-y+z二1<x-y+4z=10<3x+y-2z=247・x+3y+2z二2;+2y—z二3x+y+z=262x+3y-z=16<x-y=lxyz51・2x-y+z=18•A% J52・ 2一4一23x-y+z二4"4x-9z二172x+3y-z=12<3x+y+15z=1849・.x+y+z二6 .50.、x+2y+3z二2"x+2y+3z二5x+2y+z=2<2x+3y+6z=9 «x-4y+z二553・.5x+3y+9z二:15. 54・.2x-2y-5z=0"x+y+z二6<2x+3y+z=ll55.⑶=2y_z二2z+x56•若3 4 5,求x,y,z的值.(x二1 (x二一2(x二3对于等式ypx2+bx+c,有三对x,y的值I尸一N[y=4.(尸4能使等式两边值相等,试求a,b,+2y+3z=14‘2x+y+z二7[3x+y+2z=-y=5k己知关于x,y的方程组]x+尸k 的解也是方程4x-y=-9的解,-y=5方程组(3x-2尸°的解也是方程4x・3y+k二0的解,・已知等式y二ax2+bx+c,且当x=l时y二2;当x二・1时y=-2;当x二2时y二3,你能求出a,b,c的值吗?'4x+9y=15己知关于x,y的方程组[x+3y=2-2k的解满足3x+15y