SOLUTION: -4x+4z=24 6x+2y=-4 3y+4z=28

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Question 1152619: -4x+4z=24
6x+2y=-4
3y+4z=28
Found 2 solutions by MathLover1, Alan3354:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

-4x%2B4z=24......eq.1
6x%2B2y=-4......eq.2
3y%2B4z=28......eq.3
--------------------------

-4x%2B4z=24......eq.1....solve for+z
z=x%2B6........1a
3y%2B4z=28......eq.3...solve for+z
z=-3y%2F4%2B7........3a
from 1a and 3a we have
x%2B6=-3y%2F4%2B7....solve for y
3y%2F4=-x%2B7-6
3y%2F4=-x%2B1
3y=-4x%2B4
y=-4x%2F3%2B4%2F3.........2a
go to
6x%2B2y=-4......eq.2, substitute y from 2a

6x%2B2%28-4x%2F3%2B4%2F3%29=-4
6x-8x%2F3%2B8%2F3=-4
6x-8x%2F3=-4-8%2F3.....both side multiply by 3
18x-8x=-12-8
10x=-20
x=-20%2F10
x=-2
go to 2a, plug in x
y=-%284%28-2%29%29%2F3%2B4%2F3
y=8%2F3%2B4%2F3
y=12%2F3
y=4
go to 1a, plug in x
z=-2%2B6........1a
z=4
solutions:
x+=+-2
y+=+4
z+=+4

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
-4x+4z=24
6x+2y=-4
3y+4z=28
===============
I would use elimination.
-4x + 0y + 4z = 24
 0x + 3y + 4z = 28
---------------------- Subtract
-4x - 3y = -4 --- Eqn A
Now you have 2 eqns in x & y
================
 6x + 2y = -4
Divide by 2
 3x + 1y = -2
Multiply by 3
 9x + 3y = -6
-4x - 3y = -4 --- Eqn A
-------------------------------------- Add
5x = -10
x = -2
===============

Sub for x in Eqn A to find y
-4x+4z=24
Sub for x to find z