The composite shape shown in the picture can be divided into three forms:
1) An equilateral triangle with side length a=22ft
The area of an equilateral triangle can be determined using the following formula:
Replace it with a=22ft
2) A square with side length a=22ft
The area of the square can be determined as the square of the side length:
3) A triangle with height 22ft and base 16ft
The area of the triangle can be calculated as half the product of the base and the height:
The total area of the composite shape is equal to the sum of the three areas: