x+z=y 7z=x+y+2 x+y+z=14 解三元一次x+z=y7z=x+y+2x+y+z=14解三元一次

x+z=y 7z=x+y+2 x+y+z=14 解三元一次x+z=y7z=x+y+2x+y+z=14解三元一次
x+z=y 7z=x+y+2 x+y+z=14 解三元一次
x+z=y
7z=x+y+2
x+y+z=14
解三元一次

x+z=y 7z=x+y+2 x+y+z=14 解三元一次x+z=y7z=x+y+2x+y+z=14解三元一次
y得7

在y 7x+z=y ①
,x+y+2=7z, ②
x+y+z=14 ③
③-①得
y=14-y
2y=14
y=7
③-②得
z-2=14-7z
8z=16
z=2
把y=7，z=2带入①
2+x=7
x=5学习下

(x+y-z)(x-y+z)= fangchengzu:X+Z=Y 7Z=X+Y+Z X+Y+Z=14 x+y+z=14 7z=x+y+2 x+z=y 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? (x-2y+z)(x+y-2z)分之（y-x)(z-x) + (x+y-2z)(y+z-2x)分之(z-y)(x-y) + (y+z-2z)(x-2y+z)分之（x-z)(y-z)=?第三部分那个是 （y+z-2x)(x-2y+z)分之（x-z)(y-z) 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) 已知：x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值. x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值 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)=? (y+z)/x=(z+x)/y=(x+y)/z求x+y-z/x+y+z的值 (x+y-z)^2-(x-y+z)^2=? (x-y-z)*( )=x^2-(y+z)^2 填空 x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z 分解因式:f(x,y,z)=x^2(y-z)+y^2(z-x)+z^2(x-y) 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0