Answer:
(6,-4)
Explanation:
-3x-9y = 18 (equation 1)
4x+3y = 12 (equation 2)
multiply equation 2 by 3, and add it to equation 2
-3x-9y = 18
12x+9y = 36
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X's cancel out
9x = 54
Divide both sides by 9
x = 6
Plug in 6 for x in any of the original equations
(Plugging into Equation 2)
4(6)+3y = 12 Multiply 4(6)
24+3y = 12 Subtract 24 from both sides
3y = -12 Divide 3 on both sides
y = -4
Therefore the solution is (6,-4).