The area of the circle is 16*16*pi=256pi. We can calculate 3/4 of the circle's area for the part not represented by the triangle and the shaded area, and then add in the triangle. 3/4 of the circle's area is 192pi.
The triangle is a right triangle with two legs of length 16. Therefore, it's area is 16*16/2=128, and the total area is 192pi+128, or 731.2.