Answer:
20.3 square feet.
Explanation:
We have been given the sides of a garden. We are asked to find the area of garden using Heron's formula.
The area of a triangle with sides a, b and c would be:
, where S is the semi-perimeter of triangle.
Let us find semi-perimeter as:

Substitute given side lengths:





Therefore, the area of the garden would be 20.3 square feet.