6x²*8y²*10z²=0.314*√3

(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=4x-2y-z-5x[6y-(x+y)]+x-(3y-10z)=4x-2y-z-30xy+5x²+5xy+x-3

（1）2x+3y-4z=-5（2）x+y+z=6（两边同时×33x+3y+3z=18（与（1）相减得（5）（3）x-y+3z=10（与（2）相加得（4））（4）2x+4z=16（5）x+7z=23（两

x+y+z=A(3x+7y+z)+B(4x+10y+z)易知3A+4B=1,7A+10B=1,A+B=1,解得A=3,B=-2,所以原式=3*5-2*6=3,以后也是这样做就好了!给分吧!

此题以初中的知识不大易解!应该是你题抄错了吧,根据这类题的常型,此题条件应该是x^2+y^2-6x+2y+|z+3|+10=0,得(x-3)^2+(y+1)^2+|z+3|=0,得x=3,y=-1,z

x/10=y/8=z/9=(x+y+z)/(8+9+10)=(y+z)/(8+9)所以：(x+y+z)/(8+9+10)=(y+z)/(8+9)所以：(x+y+z)/(y+z)=(8+9+10)/(8

(1)x+y+z=6①3x-y+2z=12②x-y-3z=-4③①+②4x+3z=18④②-③2x+5z=16⑤⑤×24x+10z=32⑥⑥-④7z=14解得z=2代入⑤2x+5×2＝16解得x=3将

①代表3x+7y+z=6,②代表4x+10y+z=7,②-①得出x+3y=1,①*4,变成12x+28y+4z=24②*3,变成12x+30y+3z=21,再相减得出z-2y=3,把x+3y=1和z-

第一题2x+y+z=10x+2y+z=-6x+y+2z=8因为2x+y+z=10所以z=10-2x-y又因为x+2y+z=-6x+y+2z=8所以x+2y+10-2x-y=-6x+y+2（10-2x-

2x+y+x=10(1)x+2y+z=-6(2)x+y+2z=8(3)(1)+(2)+(3)4x+4y+4z=12x+y+z=3(4)(1)-(4),x=7(2)-(4),y=-9(3)-(4),z=

X+Y+Z=4,2*(X+Y+Z)+X=10,可以解出X=2.套入第二个和第一个.4+3Y-Z=66+2Y＋2Z＝10那么3Y=Z+2,2Y+2Z=4.Y=1,X=1X+Y+Z=4=2+1=12x+3

x-z=2.5y=7/2

2x+y+z=10(1)x+2y+z=-6(2)x+y+z=8(3)(2)-(3):y=-14(4)(1)-(2):x-y=16(5)把（4）代入（5）：x+14=16x=2(6)把（4）和（6）代入

设x/10=y/8=z/9=KX=10K,Y=8K,Z=9K（X+2Y+3Z）/（Y-5Z）=（10K+16K+27K）/（8K-45K）=-53/37

题目设置挺好的不会很变态,没什么难度由4x-3y-6z=0,x+2y-7z=0,可以解得x=3z,y=2z,将它代入代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10z=（25

x(x+y+z)=6(1)y(x+y+z)=12(2)z(x+y+z)=18(3)(1)/(2)x/y=1/2y=2x(1)/(3)x/z=1/3z=3xx(x+2x+3x)=66x^2=6x=1y=

(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)=(x+y)²+2z(x+y)+z²+(x-y)²-z²-2z(x+y)=(x+y)&

解方程可得x=3,y=5,z=1,代入可知3m+9的2009次方=10,那么m等于（10的开2009次方减去9）除以3

x+y+z=18,①8x+6y+6z=118,②2y+z=20③①×6,得6x+6y+6z=108④②-④,得2x=10x=5把X＝5代入②,得40+6y+6z=1186y+6z=78y+z=13⑤③

X+6Y+4Z+4X+4Y+Z=255X+10Y+5Z=25X+2Y+Z=5Z=5-X-2YZ=15-4X-4Y5-X-2Y=15-4X-4Y3X+2Y=10X=（10-2Y）/3X=5-2Y-ZX=

x+3y+5z=10,5x+z+3y=8两式相加6x+6y+6z=18x+y+z=3