SOLUTION: the sante fe rec. department has a 50 foot by 70 foot area for construction of a new pool. The pool will be surrounded by a concrete sidewalk of constant width. Because of water re

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Question 46665This question is from textbook advanced mathematical concepts precalculus with applications
: the sante fe rec. department has a 50 foot by 70 foot area for construction of a new pool. The pool will be surrounded by a concrete sidewalk of constant width. Because of water restrictions, the pool can have a maximum area of 2400 square feet. What should the width of the sidewalk that surrounds the pool be?
This question is from textbook advanced mathematical concepts precalculus with applications

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
50*70=3500 sq feet thus the border must be 3500-2400=1100 sq feet or
(70-2x)(50-2x)=2400 or 3500-100x-140x+4x~2=2400 or 4x~2-240x+1100=0 or
x~2-60x+275=0 or (x-55)(x-5)=0 or x=55 & X=5 THUS THE SIDEWALK IS 5 FEET WIDE