Constructing a Line Tangent to a Circle

Explanation

To construct a tangent:

1. Draw the radius to the point of tangency

2. Construct a perpendicular line at that point

3. The perpendicular line is the tangent

Important fact:

• Tangents are always perpendicular to the radius at the point of contact

Quiz (5 Questions)

1. What must be drawn first to construct a tangent?

2. What angle does a tangent make with the radius?

3. Where does the tangent touch the circle?

4. True or False: A tangent intersects the circle twice.

5. What tool is typically used to construct perpendicular lines?

Answer Key

1. The radius

2. 90°

3. One point

4. False

5. Compass or straightedge