SOLUTION: 3x-9y=12 -4x+12y=-16

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Question 1057024: 3x-9y=12
-4x+12y=-16
Found 2 solutions by Alan3354, MathTherapy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
divide the 1st eqn by 3 and the 2nd by -4

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

3x-9y=12
-4x+12y=-16
  3x -  9y = 12 ------- eq (i)

- 4x + 12y = - 16 ----- eq (ii)

Divide eq (i) by 3, and eq (ii) by 4. You can then immediately ELIMINATE x

Solve to find the value of y. 

Then find the value of x.