{x+y=3m,y+z=4m,z+x=5m(其中想x,y,z为未知数)

{x+y=3m,y+z=4m,z+x=5m(其中想x,y,z为未知数) 1、x+2y+z=4x+y+z=102x+3y-z=12、2x-3y+4m=113x+2y+5m=21x+3y+7m=20 x.y.z.m都是有理数,并且x+y+2z=m,x+2y+3z=m,那么y与z（ ） 已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z=m 若x+y+z=30,3x+y-z=50,x,y,z均为非负数,且m=5x+4y+2z,试求m的最大值与最小值. 若x+y+z=30,3x+y-z=50,x,y,z均为非负数,且m=5x+4y+2z,试求m的最大值与最小值.急,求大家快点 若x+y+z=30,3x+y-z=50,x,y,z均为非负数若X+Y+Z=30,3X+Y-Z=50,X,Y,Z均为非负数,求M=5X+4Y+2Z的取值范围.很多人做出来都是120 x+y=3m和y+z=4m和z+x=5m 求此方程解 若X+Y+Z=30,3X+Y-Z=50,X,Y,Z均为非负数,求M=5X+4Y+2Z的取值范围.最后一步不懂 已知｛x+y+z=30,3x+y+z=50.x,y,z均为非负数.求m=5x+4y+2z的取值范围.ZLMLJX好像是错的 已知:x+y+z=30,3x+y-z=50,x,y,z均为非负实数,则M=5x+4y+2z的取值范围是多少 不等式 已知x,y,z均为非零实数,x+y+z=30,3x+y-z=50 则M=5x+4y+2z取值范围是如题 若x+y+z=30,3x+y-z=50,x,y,z,均为非负数,求:m=5x+4y+2z的取值范围.说说解题思路把, 若x+y+z=30,3x+y-z=50.x,y,z均为非负数,则M=5x＋4y+2z的取值范围是xiexie 若x+y+z=30,3x+y-z=50,x,y,z皆为非负数,求M=5x+4y+2z的取值范围. 若X+Y+Z=30,3X+Y-Z=50,X.Y.Z皆为非负数,求M=5X+4Y+2Z的取值范围 若x+y+z=30,3x+y-z=50,x,y,z均为非负数,求m=5x+4y+2z的取值范围 已知x+y+z=30,3x+y-z+50,x.y.z皆为非负数,求m=5x+4y+2z的取值范围.