Question 1152619
-4x+4z=24
6x+2y=-4
3y+4z=28
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I would use elimination.
<pre>
-4x + 0y + 4z = 24
 0x + 3y + 4z = 28
---------------------- Subtract
-4x - 3y = -4 --- Eqn A
Now you have 2 eqns in x & y
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 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
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</pre>
Sub for x in Eqn A to find y
-4x+4z=24
Sub for x to find z