There is a pentagon ABCDE such that angles A, C, and E are all right angles and it is concave at angle C.

If a ray starting at D was aimed at C, it would go exactly 1 inch before going through C, and would eventually go through A.

If BC and AE are both 5 inches, what is the area of this pentagon?

AB = 13, BC = 5, CD = 1, DE = 12, EA = 5

<A = 90, <B = 67.38, <C = 270, <D = 22.62, <E = 90 (Angles measured from inside pentagon.)

Angle Sum = 540

Perimeter = 36

Area = 60

Posted by Gromit on 2004-06-25 01:23:15