Answer:
They are directly proportional.
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Explanation:
The area of a rectangle is
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Where
is length and
is width.
Now, if its width is 6 cm, then
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Now, this equation states that the area of the rectangle and its length are directly proportional, because if we increase the length, then the area will be also increased. Remember that a direct proportion between two magnitudes is where they both increase or decrease at the same time.
Therefore, they are directly proportional.