Applying the area of a rectangle, the width of the walkway (x) is: 4 feet.
What is the Area of a Rectangle?
Area of a rectangle = (length)(width)
Total area of the pool and walkway = 300 sq. ft
Length of the pool and walkway = 12 + 2x
Width of the pool and walkway = 7 + 2x
Thus, we will have the equation of the total area as:
(12 + 2x)(7 + 2x) = 300
4x² + 38x + 84 = 300
4x² + 38x + 84 - 300 = 0
4x² + 38x - 216 = 0
Factorize
(x - 4)(2x + 27) = 0
x = 4
or
x = -27/2
The width, x, cannot be negative, so, the width of the walkway (x) would be 4 feet.
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