1. How to construct a line perpendicular to a given line L through point A on L. Steps: Construction: 1. Let B be an arbitrary point on Line L 2. Construct C on Line L on the opposite side of A such that CA=CB 3. Construct equilateral triangle BCD where on line CB where D is the point of intersection 4. Draw Line AD 5. ∴ AD ⊥ L Given Line L through point A L ACB D

2. How to construct a line perpendicular to a given line L through point A on L. Steps: Construction: 1. Let B be an arbitrary point on Line L Given Line L through point A L AB

3. 2. Construct C on Line L on the opposite side of A such that CA=CB C

4. 3. Construct equilateral triangle BCD where on line CB where D is the point of intersection D

5. 4. Draw Line AD 5. ∴ AD ⊥ L