SOLUTION: solve using elimination method and check 15x+3y=-12 2x+y=8

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Question 147689This question is from textbook
: solve using elimination method and check
15x+3y=-12
2x+y=8

This question is from textbook

Found 2 solutions by mangopeeler07, GKelly:
Answer by mangopeeler07(462) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply the second equation by -3 to be able to eliminate y. You should get -6x-3y=-24. Add all that to the first equation and get 9x=-36. So x=-4. So plug that in to the second ORIGINAL equation and get 2%28-4%29%2By=8. -8%2By=8. So y=16. To check, plug them both in to either equation. 15%28-4%29%2B3%2816%29=-12. -60%2B48=-12. It's true, so x=-4 and y=16.

Answer by GKelly(4) About Me  (Show Source):
You can put this solution on YOUR website!
For elimination do the following:
Rewrite the first equation 15x + 3y = -12. Below that multiply -3 times the entire second equation to arrive at -6x - 3y = -24. When you line them up you will be able to cancel out the 3y and solve for x.
15x + 3y = -12
-6x - 3y = -24 Now cancel out the 3y and solve for x
You'll end up with 9x = -36, x = -4
Now plug -4 into the x value in the first equation and solve for y.
15(-4) + 3y = -12, -60 + 3y = -12, 3y = -12 + 60, 3y = 48, y = 16.
Take the first equation and where x is you plug in -4 and where y is you plug in 16.
15(-4) + 3(16) = -12
-60 + 48 = -12
-12 = -12
You're done!