若|x|=2,|y+3|=1,3a^3z-1·b与5ba^5能够合并,求y-2x+z的值.如题,请快些

若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 若x+y+z=3y=2z,则x/x+y+z=? 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 x+y+z=6 x+2y+3z=14 y+1=z 若x:y:z=3:2:1,则x+2y-z/2x-y+z= 已知x+y+z=3a,（a≠0,x,y,z不全等）.求（x-a)(y-a)+(y-a)(z-a)+(z-a)(x-a)／(x-a)^2+（y-a）^2+（z-a）^2 x+y+z=3a(a不等于0,x,y,z不全相等）求[（x-a)(y-a)+(y-a)(z-a)+(z-a)(x-a)]/[(x-a)^2+(y-a)^2+(z-a)^2] 已知X+Y+Z=3a求(X-a)(Y-a)+(Y-a)(Z-a)+(Z-a)（X-a)/(X-a)2;+（Y-a)2;+（Z-a)2;,a≠0,X,Y,Z不全相等, 若xyz=1,求证 x^2/(y+z)+y^2/(z+x)+z^2/(x+y)≥3/2 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 计算下面的分式题.急,我是初一的,1、(y-z)(z-x)/[(x+z-2y)(x+y-2z)]+(z-y)(x-z)/[(x+y-2z)(y+z-2x)+(x-z)(y-z)]/[(y+z-2x)(x+z-2y)]2、若a/b=b/c=c/d=d/a,则(a-b+c-d)/(a+b-c+d)的值.3、若x/(x^2-mx+1)=1,求x^3/(x^6-m^3x^3+1)的值.4、如果 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) matlab解对数方程组[x,y,z]=solve('0.29744*x/(3+0.1*x+y+z)=(log10((3+x+y+z)/(3+0.1*x+y+z)))^2','0.79*x/(3+0.1*y+z)=(log10((3+x+y+z)/(3+0.1*x+y+z)*(3+y+z)/(3+0.1*y+z)))^2','1.25*x/(3+0.1*z)=(log10((3+x+y+z)/(3+0.1*x+y+z)*(3+y+z)/(3+0.*1y+z)*(3+z)/ 求解一道数学题若x+y+z+3=2(根号x+根号y+1+根号z-1),求（x+y+z)的（y-z）次方 若x+y+z+3=2(根号x+根号y+1+根号z-1）求（x+y+z）y-z {x+y+z=1;x+3y+7z=-1;z+5y+8z=-2