What’s the area of the shaded region?

Answer:
The area of the whole cirlce should be: S = πr² = 3.14 . 5² = 78.5 (yd²)
The area of the triangle inside the cirlce should be: S = hb/2 = 7(4 . 2)/2 = 28 (yd²)
Now to find the area of the shaded region we just need to subtract the area of the cirle to the area of the triangle: 78.5 - 28 = 50.5 (yd²)