Answer:
(a) 18.5ft
(b) 388.5 ft²
Step-by-step explanation:
(a)
She has 79ft of fence = the perimeter will be 79.
Perimeter of a rectangle = 2(length) +2(width)
79 = 2(21)+2(width)
2(width) = 79 - 42
width = 37/2
width = 18.5ft
(b)
Area of a rectangle = (length)(width) = (21)(18.5) = 388.5 ft²
