Answer: Choice D) As the side length increases by 1, the area increases and then decreases by an equal factor
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Step-by-step explanation:
Choice A is ruled out because the area does change. As x changes, y changes as well. This rules out choice B as well.
Choice C is somewhat close. However, it's not entirely true since the area doesn't increase by the same amount. For instance, the jump from points (2,18) to (3,24) indicate that the jump in y value is +6. But going from (3,24) to (4,28) shows a jump of +4 in the y value. So we can rule out choice C.
This means that choice D is the final answer.