First, we need to find the area of the unshaded part
The unshaded part is a triangle
[tex]A=\frac{1}{2}\times b\times h[/tex][tex]=\frac{1}{2}\times6\times6[/tex][tex]=18ft^2[/tex]
The triangles are 2
Area of the two triangles = 18ft² + 18ft² = 36ft²
We can now proceed to find the total area (area of the rectangle)
[tex]A=l\times w[/tex]
[tex]=20\times9\frac{1}{4}[/tex][tex]=20\times\frac{37}{4}[/tex][tex]=185ft^2[/tex]
Area of the shaded part = Total area - area of the unshaded part
= 185ft² - 36ft²
= 149 ft²
