SOLUTION: x-4y+3z=-27 2x+2y-3z=22 4z=-16

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Question 14059: x-4y+3z=-27
2x+2y-3z=22
4z=-16
Answer by rahman(247) About Me  (Show Source):
You can put this solution on YOUR website!
4z=-16
4z%2F4=-16%2F4
z=-4
Substitute z= -4 to the first and the second equation:
x-4y+3z=-27
x-4y+3(-4)=-27
x-4y-12=-27
x-4y=-27+12
x-4y=-15 ..........(i)
2x+2y-3z=22
2x+2y-3(-4)=22
2x+2y+12=22
2x+2y=22-12
2x+2y=10 --------->divide by 2
x + y = 5 .........(ii)
Use elimination method:
x-4y=-15
x+y = 5
-------- -
-5y=-20
%28-5y%29%2F%28-5%29=%28-20%29%2F%28-5%29
y=4
Substitute y=4 to (ii):
x + y = 5
x + 4 = 5
x = 1
So, the solution are x=1, y=4 and z=-4
OK