Hree you have a small ( the clear triangle) inside a large one.
Area = shaded part = area of large triangle - area of the small clear triangle.
Area of a triangle = 1/2 * base * height
so we have area shaded part = 1/2 * 6 * 9 - 1/2 * 2 * 3
= 27 - 3 = 24 yd^2 Answer