Question 1153511
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paint a 45-square-foot rectangular 
mural on a wall that is 13 feet long and 9 feet high,...
.....leave a border of uniform width
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Mural length 13-2w
Mural height 9-2w
{{{highlight_green((13-2w)(9-2w)=45)}}}


If the solution is in whole numbers, you could look for factors of 45 which differ by 4.



Dimensions 9 and 5
;
{{{9-2w=5}}}