CCGPS AG 3.3.1 Example 3

Use a compass and a straightedge to construct the lines tangent to circle at point .

  1. Draw a ray connecting center and the given point .
  2. Find the midpoint of by constructing the perpendicular bisector.
  3. Put the sharp point of the compass on midpoint and open the compass to point . Without changing the compass setting, draw an arc across the circle so it intersects the circle in two places. Label the points of intersection as and .
  4. Use a straightedge to draw a line from point to point and a second line from point to point .

– Walch Education, GeoGebra Materials Team