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solve the system by addition:
-5x-9y = -5

I've tried this one over and over, but I can't seem to get the right answer. I don't even really know where to start. each time i try to do it, i go about it a little differently and i'm completely lost, pls help!!

from the second equation:
now sub that back in the first one:
now sub that back into x=-5y-15

first equation .....
-5x - 9y = -5
second equation times 5 ...
5x + 25y = -75

add them, the x's are eliminated

16y = -80
y = -5
substitute that in one of the originals, etc

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