The expression for the area of the rectangular swimming pool is given as follows:
A = w² + 100w + 2100.
The area of a rectangle of length l and width w is given by the multiplication of these measures, that is:
A = lw.
In this problem, considering the width of 70 meters and a length of 30 meters, plus the floor of w meters, we have that:
Hence the area is given as follows:
A = l x wi = (30 + w)(70 + w) = w² + 100w + 2100.
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