SOLUTION: I do not understand this: Solve the following system of equations: 2x+3y-x=0 X-2y-4z=14 3x+y-8z=17 This is all one problem.I'm having trouble and need some guidance if you

Algebra.Com
Question 1047631: I do not understand this:
Solve the following system of equations:
2x+3y-x=0
X-2y-4z=14
3x+y-8z=17
This is all one problem.I'm having trouble and need some guidance if you could please to make this a little more simple for me to understand. Thank you so much for you time and help.

Found 2 solutions by ikleyn, stanbon:
Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.
I suspect that your first equation is written incorrectly.
Check it. Fix it, if necessary.
Then re-submit.


Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Solve the following system of equations:
2x+3y-x=0
X-2y-4z=14
3x+y-8z=17
Interchange row 1 and row 2 to get:
-------------------
X-2y-4z=14
2x+3y-x=0
3x+y-8z=17
Subtract 2*row 1 from row 2
Subtract 3*row 1 from row 3
----------------------
x - 2y - 4z = 14
0 + 7y +7z = -28
0 + 7y -5z = 17
---------------------------
Subtract row 2 from row 3 to get:
x - 2y - 4z = 14
0 + 7y + 7z = -28
0 + 0 -12z = 45
-------------------------
Solve row 3 for "z"
z = -15/4
------
Divide thru row 2 by 7 to get::
x - 2y - 4z = 14
0 + y + z = -4
-----------------------------
Substitute for "z" and solve for "y"::
x - 2y - 4z = 14
y = -4+15/4
y = -1/4
---------------------
Substitute for y and z in row 1 and solve for "x":
x - 2(-1/4) - 4(-15/4) = 14
-------------------
x + (1/2) + 15 = 14
x = -3/2
---------------------
Cheers,
Stan H.
---------------

RELATED QUESTIONS

{{{system(2x+3y-z=0, x-2y-4z=14, 3x+y-8z=17)}}} (answered by Edwin McCravy)
These are solutions of three equations in three variables. i don't understand this at... (answered by Alan3354,josmiceli)
hi my name is brittny and i am having trouble with this one problem directions: solve... (answered by wuwei96815)
Hello I am trying to do my math homework and there are still questions that I just don't... (answered by Alan3354)
This is a homework assignment and I have been trying to solve it with no luck. The... (answered by stanbon)
how do you solve this system of equations: 2x-3y+z=5 x+3y+8z=22... (answered by jim_thompson5910)
I need to solve the following system of linear equations with three variables. Here is... (answered by ptaylor)
Solve the following system: x-3y+4z=7 2x+3y-6z=5... (answered by stanbon)
solve the following system of linear equations: 3x-2y+4z=1 x+y+2Z=3... (answered by longjonsilver)