1. Prove one of the theorems about isosceles triangles
2. Prove another of the theorems about isosceles triangles.
3. Given that /AOE = 38o, O is the center of the circle, NO | OE, NO || AP, and NE is tangent to the circle at A,
4. Given a triangle, construct the three perpendicular bisectors, the three angle bisectors, the three medians and the three altitudes. Draw in the circumscribed circle, the inscribed circle, and the Euler line.
5. Given that DE || BC, AB = 8, BC = 12, AD = 5, find DE.