Trisecting an angle using origami

1. Divide the bottom half of your square to quarters. Unfold.

2. Select your angle by folding line L from the bottom left-hand corner to any point on the top side of your square. Unfold.

3. Now fold the bottom left-hand corner up so that point P (point P is the intersection of the half-line with the left-hand side of your square) touches line L while at the same time the bottom left-hand corner touches the bottom quarter-line.

4. To form the trisecting line T, simply extend the bottom quarter-line (now at an angle) through the rest of the paper. Unfold.

Ophir Feldman