Question 1136535
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I will assume that the two side of the garden along which the sidewalk is to be put are two adjacent sides, rather than two opposite sides....<br>
The width and length of the garden are x and 2x+5.<br>
The lengths of the 3-foot-wide sidewalks are x and 2x+5 along those two sides.<br>
And on the corner where the two sidewalks meet there will be a 3x3 square of sidewalk.<br>
Then, since the total area of the sidewalk is 213 square feet,<br>
{{{3(x)+3(2x+5)+3(3) = 213}}}
{{{3x + 6x+15 + 9 = 213}}}
{{{9x + 24 = 213}}}
{{{9x = 189}}}
{{{x = 21}}}<br>
The dimensions of her garden are x = 21 feet by (2x+5) = 47 feet.