SAT Subject Test Mathematics Level 1

Figure  5

Once again, the key here is to add to the figure. And in this case, as so often
when there’s a circle, what you should add is radii. The equilateral triangles
tell you that the central angles are 60° and 120°.

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

circle  is  1   and AB  =   1,  what    is  the area    of  the shaded  region?

1.

(A) 0.091

(B) 0.285

(C) 0.614

(D) 0.705

(E) 0.732