Question 264432
how do i slove this system 
3x+5y=-3
10y-2z=2
x=-z
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Sub -x for z in the 2nd eqn, then it's a 2 eqn system.
3x+5y=-3 --> 6x+10y=-6
10y+2x=2
--------
6x+10y=-6
2x+10y=2
-------- Subtract
4x = -8
--------
Take it from there.