Question 1199222
Total area,  {{{4*8}}} square meters
Area of remaining plot for the flowers, {{{(4-2w)(8-2w)}}} for w uniform width border


{{{(4-2w)(8-2w)=12}}}
Solve for w.


Simplify first...

{{{2*2*(2-w)(4-w)=2*2*3}}}

{{{(2-w)(4-w)=3}}}
Could these factors of 3 be  1 and 3 ?
Trying this,
{{{2-w=1}}}
{{{2-1=w}}}
{{{w=1}}}
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OR
{{{4-w=3}}}
{{{4-3=w}}}
{{{w=1}}}
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The uniform width of the inside border is 1 {{{cross(foot)}}}meter.