SAT Subject Test Mathematics Level 2

Consider Example 6.

Example 6

Figure  5

As usual, the key here is to add to the figure. And here, as is so often the case with circles, you should
add radii. The equilateral triangles formed by and the radii, and by and the radii, have
central angles of 60º.

In  Figure  5,  rectangle   ABCD    is  inscribed   in  a   circle. If  the radius  of  the circle  is  2   and     =   2,

what    is  the area    of  the shaded  region?

6.

(A) 0.362

(B) 0.471

(C) 0.577

(D) 0.707

(E) 0.866