x:16=15:y=z:80=百分之125 解出未知数

x:16=15:y=z:80=百分之125 解出未知数 (x+y-z)(x-y+z)= 解方程 x(x+y+z)=6 y(x+y+z)=12 z(x+y+z)=18 解方程组{x(x+y+z)=6,y(x+y+z)=12,z(x+y+z)=18 2x+y+z=15 x+2y+z=16 x+y+2z=17 解方程组:2x+y+z=15 x+2y+z=16 x+y+z=17 x+y=16 y+z=12 z+x=10 求x,y,z等于多少? 20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z= x+y=8 y+z=12 x+z=10 x+y+z= x+y=8 y+z=12 x+z=10 x+y+z= x+y+z=15 x+5y+10z=70 x,y,z,各是几? x+y+z=15 x+5y+10z=70 x,y,z,各是几? X+Y-Z=15 X+5Y+10Z=70 求：X、Y、Z {x+z+y=15 z+x+w=18} {y+x+w=16 w+z+y=17} ,求x.y.z.w各是多少? X+Y+Z=? x/y=(x+z)/(y+z)y/z=(x+y)/(x+z) 已知 x/(y+z)+y/(z+x)+z/(x+y)=1求 (x*x)/(y+z)+(y*y)/(x+z)+(z*z)/(x+y)=? x+y+z=12 x-y+z=2 x-z+y+a=90 x+y+a+z=100,求x y z a