Looking at the top half, we can see a triangle formed by ABC.
The area of a triangle is found by multiply 1/2 x base x height.
The height would be 1/2 of the overall height of the shape so 14.3 /2 = 7.15.
The area of the top half = 1/2 x 7.15 x 17.2 = 61.49
Since the bottom half is identical to the top half, multiply that area by 2 for the total area:
61.49 x 2 = 122.98 square feet.