3x+2y-z=1,2x-y+2z=5,5x-2y+3z=13
来源:学生作业帮助网 编辑:六六作业网 时间:2025/01/29 06:20:07
3x+2y-z=1,2x-y+2z=5,5x-2y+3z=133x+2y-z=1,2x-y+2z=5,5x-2y+3z=133x+2y-z=1,2x-y+2z=5,5x-2y+3z=133x+2y-z
3x+2y-z=1,2x-y+2z=5,5x-2y+3z=13
3x+2y-z=1,2x-y+2z=5,5x-2y+3z=13
3x+2y-z=1,2x-y+2z=5,5x-2y+3z=13
3x+2y-z=1 ①
2x-y+2z=5 ②
5x-2y+3z=13 ③
由③+①得:
8x+2z=14
即4x+z=7 ④
由①+②×2得:
7x+3z=11 ⑤
由④×3-⑤得:
5x=10
x=2
把x=2代入④得:
8+z=7
z=-1
把x=2,z=-1代入②得:
4-y-2=5
y=-3
所以方程组的解为:x=2 y=-3 z=-1
3x+2y-z=1 (1)
2x-y+2z=5 (2)
5x-2y+3z=13 (3)
(1)*2+(2):
6x+4y-2z+2x-y+2z=7
8x+3y=7 (4)
(1)*3+(3):
9x+6y-3z+5x-2y+3z=16
全部展开
3x+2y-z=1 (1)
2x-y+2z=5 (2)
5x-2y+3z=13 (3)
(1)*2+(2):
6x+4y-2z+2x-y+2z=7
8x+3y=7 (4)
(1)*3+(3):
9x+6y-3z+5x-2y+3z=16
14x+4y=16
7x+2y=8 (5)
(5)*3-(4)*2:
21x+6y-16x-6y=24-14
5x=10
x=2
代入(4):
16+3y=7
y=-3
代入(1):
6-6-z=1
z=-1
所以:
x=2
y=-3
z=-1
收起
x/2=y/3=z/5 x+3y-z/x-3y+z
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
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)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z
已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值
已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值
已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX..
x+y+z=6 x+2y+3z=14 y+1=z
方程组 (1) x+2y-3z=12 x-3y+2z= - 13 x-y-z=0 (2) x+ y=z 5x-y+z=18 2x+5y+3z= -1
x+Y+Z=1 X+3Y+7Z=-1 X+5Y+8Z=2x+Y+Z=1X+3Y+7Z=-1X+5Y+8Z=2
若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值
x+y+z=2 x-3y+2z=1 2x+2y+z+5 要具体步骤..
3x-y+2z=-1 4x+y+z=5 x-2y-z=-2
{x+y+z=1 x-2y+3z=5 2x-3y-3z=-8
2x-y+3z=3 {3X+Y-2Z=-1 X+Y+Z=5
x-y+z=-1 5x+2y-z=6 4x-3y+2z=-5
x+y+z=-5,3x+y+z=1,4x+3y+2z=-2快
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5