已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值

来源：学生作业帮助网 编辑：六六作业网 时间：2024/08/11 05:19:22
已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值已知2x+5y+4z=15,7x+y+3z=14,求4x+y

已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值
已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值

已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值
2x+5y+4z=15,.(1)
7x+y+3z=14.(2)
(2)*4-(1)*3,得
22x-11y=11
2x-y=1
y=2x-1
(2)*5-(1),得
33x+11z=55
3x+z=5
z=5-3x
所以
4x+y+2z
=4x+(2x-1)+2(5-3x)
=4x+2x-1+10-6x
=9

2x+5y+4z=15,(1);7x+y+3z=14,(2);由(1)+(2)*6得:(2+7*6)x+(5+6)y+(4+3*6)=15+16*6,即44x+11y+22z=99,化简得:4x+y+2z=9

已知2x+5y+4z=6 3x+y-7z=-4求x+y-z 已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值 已知关于x y z的方程组2x-3y+5z=7 x+2y-3z=8,则4x+y-z= 已知4x-3y-6z=0,x+2y-7z=0,求5x+2y-z/2x-3y-10z 已知x:y:z=4:5:7,求:(1)2x+3y+z/5z; (2)x+y/y+z. 1.已知x:y:z=4:5:7,求：（一）2x+3y+z/5z； （二）x+y/y+z 非常急, 已知5x=3y,4z=7y,求x:y:z 已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z=m 已知2x+5y+4z=15,7x+y+3z=14,求4x+2y+2z的值 已知2x+5y+4z=15,7x+y+3z=14,求4x+y+2z的值 已知2x+5y+4z=15,7x+y+3z=14,求4x+y+z等于多少? 已知(x+2y)/3=(y+3z)/4=(z+5x)/5,则x:y:z= 已知x+2y/3=y+3z/4=z+5x/5,则x:y:z=? 已知x+2y/3=y+3z/4=z+5x/5,则x:y:z= 已知4X=7Y+5Z,2X+Y=Z,那么X:Y:Z的值是? 已知4X=7y+5z,2x+y=z,那么x:y:z的值是? 已知x,y,z,满足方程组x-2y+z=0,7x+4y-5z=0 已知{x-5y+2z=0 3x-5y-4z=0,求x：y:z