There are two pieces we need to find here: the area of the section of the circle, and the area of the triangle.
Area of the section of the circle:
A = pi * r^2
A = pi * 15^2
A = 225pi * 72/360 || We only need this part of the circle, not the whole thing.
A = 45pi
Area of the triangle:
A = 1/2 * a * b * sin(c)
A = 1/2 * 15 * 15 * sin(72)
A = 112.5 * sin(72)
Next, we need to subtract the area of the triangle from the area of the section of the circle.
A = 45pi - (112.5 * sin(72))
A = 112.8165 units^2 -- Feel free to round off wherever you need!
Hope this helps!! :)