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?

Angle C is a right angle?
it is concave at angle C?

I thought concave implied an angle greater than 180; so either there's a typo, or my definition of "concave" is wrong.

Posted by Larry on 2004-06-12 11:30:44