已知x:y=1:2y:z=2:3x+y+z=27
已知x−y+z=0x+2y−3z=0
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
已知有理数x,y,z,且|x-3|+2|y+1|+(2z+1)²=0,求x+y+z的相反数的倒数.
有关分式的数学题1、已知X/3=Y/5=Z/4,求(X+Y+Z)/Y和(X+Y+Z)/(Y-Z)的值.2、甲乙两人分别从
已知方程组x:y:z=1:2:7 2x−y+3z=42
x+2y+3z=12x+3y+z=23x+y+2z=3
2x+y+3z=383x+2y+4z=564x+y+5z=66
x+y−2z=52x−y+z=42x+y−3z=10
若x+2y-4z=0 3x+y-z=0 求x:y:z
已知2/x=4/y=7/z,求(1)x:y:z(2)若2x+y+3z=58,分别求x,y,z的值.
已知 x,y,z都是正实数,且 x+y+z=xyz 证明 (y+x)/z+(y+z)/x+(z+x)/y≥2(1/x+1
xy/x+y=1,yz/y+z=2,xz/x+z=3求x,y