# algebra

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solve system of equation

5x+2y+z=-25
5x-3y-z=-23
3x+y+2z=-9

• algebra -

I would use elimination and start with the z's
Add the first plus the second to get
10x - y = -48

Double the second and add it to the third to get 13x - 5y = -55

ahhh, changed my mind, let's now switch to substitution
from above 10x - y = -48 or
y = 10x + 48

sub that into
13x - 5y = -55
13x - 5(10x + 48) = -55

etc. (I got x=5)

I am sure you can finish it from here.

• algebra -

I am coming up with (-5,-2,4) for my answer and I see you x=5

• algebra -

good job
You can tell your answers are correct by merely subbing them back into the 3 original equations, they work

TRUST YOURSELF

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