Answer:
A. 8y = -6
Step-by-step explanation:
Add by going down, like you would add any large number.
x + 6y = 9
-x + 2y = -15
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0 + 8y = -6
In words, you can think x - x = 0, 6y + 2y = 8y, and 9 - 15 = -6.
Put these all together, and you get 8y = -6
