How can you divide an angle into 3 equal angles? You may only use a straightedge
and a compass to achieve this.
(This means : You have an angle A, you divide Angle A into 3 Angles B,C,D. And B=C=D=A/3)
Note: vohonam clarified that the problem actually only gives you a straightedge, not a ruler.
I thought I have heard that the trisecting of an angle with compasses and ruler is impossible. Wasn't it one of the great puzzles man had in ancient times. (Or has modern man found it?)