Answer:
x = 3; y = -6
Step-by-step explanation:
x - 2y = 15
2x + 4y = -18
Multiply both sides of the first equation by 2. Write the second equation below it, and add the two equations.
2x - 4y = 30
(+) 2x + 4y = -18
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4x = 12
4x/4 = 12/4
x = 3
Now we substitute 3 for x in the first equation and solve for y.
x - 2y = 15
3 - 2y = 15
-2y = 12
y = -6
Answer: x = 3; y = -6
