Question 762029
Grass strip + the court = 900 sq. ft.
The court by itself is {{{30*50=1500}}} sq. ft.


The grass strip + the court is some unknown width, w more than the border between grass strip and court.  This whole combined area is {{{(30+2w)(50+2w)=1500+900}}} sq. ft. 


{{{2*2(15+w)(25+w)=2400}}}
{{{(15+w)(25+w)=600}}}
{{{15*25+15w+25w+w^2=600}}}
{{{w^2+40w+375=600}}}
{{{w^2+40w-225=0}}}

{{{highlight((w+45)(w-5)=0)}}}
One of the solutions will make sense and the other will not make sense.
{{{highlight(w=5)}}} feet.

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