4X+9Z=12 {3Y-2Z=17X+5Z=4又4分之33X-Y+2Z=3{2X+Y-3Z=11X+Y+Z=66

来源：学生作业帮编辑：搜搜考试网作业帮分类：数学作业时间：2024/08/02 22:54:58

4X+9Z=12
{3Y-2Z=1
7X+5Z=4又4分之3
3X-Y+2Z=3
{2X+Y-3Z=11
X+Y+Z=66

4X+9Z=12 (1)
3Y-2Z=1 (2)
7X+5Z=4又4分之3=19/4 (3)
(1)*5-(3)*9
20X+45Z-63X-45Z=60-9
-43X=51
X=-51/43
Z=(12-4X)/9=80/43
Y=(1+2Z)/3=203/129
3X-Y+2Z=3 (1)
2X+Y-3Z=11 (2)
X+Y+Z=66 (3)
(1)+(2)
5X-Z=14 (4)
(1)+(3)
4X+3Z=69 (5)
(4)*3+(5)
15X-3Z+4X+3Z=42+69
19X=111
X=111/19
Z=5X-14=289/19
Y=66-X-Z=854/19

x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 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:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. x+2y+4z=17 2x+y+z=7 3x+y+2z=11 已知2x=3y=4z求2x-y+z分之x+y+z的值已知x:y:z=2:3:4求x-y+z分之x+y-z的值 x/2=y/3=z/5 x+3y-z/x-3y+z x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=? 1.x+y=16,y+z=12,z+x=102.3x-y+z=4,2x+3y-z=12,x+y+z=63.x+y+z=6 2x-y+2z=-17 3x+y-3z=-4 x+y+z=6 解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6} 解方程{3x -y+z=4 2x+3y-z=12 x+y+z=6