Answer: rational
Step-by-step explanation:
-6 can be written as such an infinite number of ways (just as any rational can be). For example, -6/1, 6/-1, 12/-2, -666/111 and so indeed -6 is rational.

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Answer:
x = 0
y = -2
Step-by-step explanation:
-5x + y = -2
x = 0
y = -2
-3x + 6y = -12
x = 0
y = -2