Answer:
7 ft
Explanation:
Perimeter of a rectangle is denoted by the formula:
, where l is the length and w is the width.
We know that P = 20 and that w = 3. So, let's plug these values in:
Isolate the variable
by subtracting 6 from both sides and dividing by 2:
Thus, the answer is 7 feet.
Hope this helps!