Answer:
[tex]r=\sqrt{106}\ cm[/tex]
Step-by-step explanation:
see the attached figure to better understand the problem
Applying Pythagoras Theorem in the right triangle ODB find the radius of the circle
[tex]r^{2}=9^{2}+5^{2}[/tex]
[tex]r^{2}=81+25[/tex]
[tex]r=\sqrt{106}\ cm[/tex]
