Respuesta :

Area of the quarter sector 
Area of the entire circle = pi * r^2
Area of the quarter circle = pi r^2 / 4
r = 9
Area of the quarter circle = pi 9^2 / 4
Area of the quarter circle = pi 81/4 = 20.25 pi

Area of the triangle
Area pf the triangle = 1/2 b*h
b = h = r
r = 9
Area of the triangle = 1/2 9 * 9 
Area of teh triangle = 1/2 81
Area of the triangle = 40.5

Area of the shaded area
The shaded area = Area of the 1/4 circle - area of the triangle
The shaded area = (20.24 pi - 40.5)ft^2

 A <<<<<< Answer.