SOLUTION: Does the system have a solution? If so, could you help me find it? x+y=9 5x+y=29 x-y=2 How do I graph the function f(x)=[x-2]+3? How do I solve the system : x-y+z=1

Algebra ->  Matrices-and-determiminant -> SOLUTION: Does the system have a solution? If so, could you help me find it? x+y=9 5x+y=29 x-y=2 How do I graph the function f(x)=[x-2]+3? How do I solve the system : x-y+z=1      Log On


   



Question 472985: Does the system have a solution? If so, could you help me find it?
x+y=9
5x+y=29
x-y=2

How do I graph the function f(x)=[x-2]+3?

How do I solve the system :
x-y+z=1
2x+2y=4
-x+4y+3z=6
Thank you for your time.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=9
5x+y=29
x-y=2
----
You have 3 equations with 2 variables.
Adding the 1st and 3rd you get 2x = 11
x = 5.5
----
Using x+y = 9, y = 3.5
---
Trying that in the 2nd equation you would get:
5(5.5) + 3.5 = 29
27.5 + 3.5 = 29
31 = 29
Wrong.
The three lines do not meet at a point so there is
no solution for the system.
------------------------------------------
How do I graph the function f(x)=[x-2]+3?
---
Is that supposed to be absolute (x-2)?
------------------------------------------
How do I solve the system :
x-y+z=1
2x+2y+0z=4
-x+4y+3z=6
---
Divide thru the 2nd equation by 2
How do I solve the system :
x-y+z=1
x+y+0z=2
-x+4y+3z=6
---------------
Subtract the 1st equation from the 2nd.
Add the 1st equation to the 3rd.
-------------------
x-y+z=1
0x+2y-z=1
0x+3y+4z=7
----------------------
Divide thru the 2nd equation by 2.
---
x-y+z=1
0x+y-(1/2)z=(1/2)
0x+3y+4z=7
---------------
Subtract 3 times the 2nd equation from the 3rd:
x-y+z=1
0x+y-(1/2)z=(1/2)
0x+0y+(11/2)z=11/2
------------------
Solve for "z" in the 3rd equation:
x-y+z=1
0x+y-(1/2)z=(1/2)
0x+0y+z=1
==============
Use z=1 to solve for "y" in the 2nd equation:
y-(1/2) = 1/2
y = 1
-------
Use z = 1 and y = 1 to solve for "x" in the 1st equation:
x -1+1 = 1
x = 1
------
Solution:
x = y = z = 1
===================
Cheers,
stan H.