Answer:
The dimensions of rectangular fence are 14 feet and 20 feet.
Step-by-step explanation:
We are given the following in the question:
Length of rectangular fence = 14 feet
Width of fence = (14+x) feet
Area of rectangular field = 280 square feet
Area of rectangular field =

Putting the values, we get,

Thus, the dimensions of rectangular fence are 14 feet and 20 feet.