Question 1134642
u, the uniform width surrounding the flower bed
A, the area of the border surrounding the flower bed

{{{(18-2u)(22-2u)-18*22=A}}}


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If 1 plant needs 1 square foot, and if 384 of the low growing plants, then this means border containing the low grow plants must be 384 square feet.
{{{(18-2u)(22-2u)=384+18*22}}}
Simplify and solve.


{{{2*2*(9-u)(11-u)=780}}}

{{{2*2*(9-u)(11-u)=4*195}}}

{{{(9-u)(11-u)=195}}}

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Note that {{{195=13*15}}}, and the two binomial factors on the left differ by two.