Answer: Geometric
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Step-by-step explanation:
To go from term to term, we are multiplying by 2
-7 * 2 = -14
-14 * 2 = -28
-28 * 2 = -56
This means the common ratio is 2 and this sequence is geometric.
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Alternatively, you can divide each term by its prior term
-56/(-28) = 2
-28/(-14) = 2
-14/(-7) = 2
Each time we get the same result showing the common ratio is 2.