Answer:
28 ft
Step-by-step explanation:
Let longer side of rectangle be
and the shorter side be
, thus we can write the ratio:

<em>Now putting 21 into S, we solve for L:</em>

Hence, length of longer side is 28 ft.
30 or 3 and 4 weeks hope this helps
Length (L): 2w + 3
width (w): w
border (b): 
Area (A) = (L + b) * (w + b) <em>NOTE: This is assuming the width also has a border</em>
= (2w + 3 +
) * (w +
)
= 

= 

= 