Answer: The pool is 30 feet by 15 feet
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Step-by-step explanation:
x = width
2x = length, since it is twice as long as it is wide
area = length*width = 2x*x = 2x^2
Set this equal to the area of 450 sq ft and solve for x
2x^2 = 450
x^2 = 450/2
x^2 = 225
x = sqrt(225)
x = 15 feet is the width
2x = 2*15 = 30 feet is the length
Check:
area = length*width = 30*15 = 450
The answers are confirmed.