Example 1

Use a compass and a straightedge to construct tangent to circle at point .
  1. Draw a ray from center through point and extending beyond point .
  2. Put the sharp point of the compass on point . Set it to any setting less than the length of , and then draw an arc on either side of , creating points and .
  3. Put the sharp point of the compass on point and set it to a width greater than the distance of . Make a large arc intersecting .
  4. Without changing the compass setting, put the sharp point of the compass on point and draw a second arc that intersects the first. Label the point of intersection with the arc drawn in step 3 as point .
  5. Draw a line connecting points and , creating tangent .
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