SOLUTION: 3x-4y-z=1 x-y+3z=3 3x-2y+2z=0 Solve by adding/subtracting elimination method

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Question 956003: 3x-4y-z=1
x-y+3z=3
3x-2y+2z=0
Solve by adding/subtracting elimination method
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

3x-4y-z=1.....eq.1
x-y%2B3z=3.....eq.2
3x-2y%2B2z=0.....eq.3
----------------------------
3x-4y-z=1.....eq.1
3x-2y%2B2z=0.....eq.3
-----------------------------------subtract
3x-4y-z-%283x-2y%2B2z%29=1-0
cross%283x%29-4y-z-cross%283x%29%2B2y-2z=1
-2y-3z=1....solve for y
-1-3z=2y
y=-%283%2F2%29z-1%2F2
y=-1.5z-0.5...substitute in

x-y%2B3z=3.....eq.2
x-%28-1.5z-0.5%29%2B3z=3
x%2B1.5z%2B0.5%2B3z=3
x%2B4.5z=3-0.5
x=-4.5z%2B2.5....
go to 3x-4y-z=1.....eq.1 substitute x and y
3%28-4.5z%2B2.5%29-4%28-1.5z-0.5%29-z=1...solve for z
-13.5z%2B7.5-%28-6z-2%29-z=1
-13.5z%2B7.5%2B6z%2B2-z=1
-8.5z%2B9.5=1
-1%2B9.5=8.5z
8.5=8.5z
highlight%28z=1%29
now we can find x and y
x=-4.5z%2B2.5
x=-4.5%2A1%2B2.5
highlight%28x=-2%29
y=-1.5z-0.5
y=-1.5%2A1-0.5
highlight%28y=-2%29