Study the following diagram, where point W lies on circle O.
Point C lies in the exterior of circle O.
Segment WC is tangent to circle O at point W.
CO¯¯¯¯¯¯¯¯, CW¯¯¯¯¯¯¯¯¯, and OW¯¯¯¯¯¯¯¯¯ are drawn in to create △OWC.
Circle O as described, where segment O W is labeled r.
If OW=9 and WC=12, what is CO?
Enter the correct value.
