Answer:
173
Explanation:
Area of dirt in the flower bed = area of flowerbed - area of 3 trapezoids
Area of flowerbed:
The flowerbed is in the shape of a parallelogram
The area of a parallelogram can be calculated by multiplying the base length times the height
Base length = 20ft
Height = 10ft
Area of flowerbed = 10 * 20 = 200ft^2
Area of rockbeds
The rockbeds are in the shape of trapezoids
The area of a trapezoid can be calculated using this formula
A = (a + b)/2 * h
Where a and b = bases and h = height
The rockbeds of base lengths of 2 and 4 and have heights of 3
So area of rockbeds = (4 + 2)/2 * 3
4 + 2 = 6
6 / 2 = 3
3 * 3 = 9
We then multiply that by 3 ( because there are three rockbeds )
9 * 3 = 27
Finally we subtract the areas
200 - 27 = 173