Answer:
/BO/=|OC|[Rdius]
AO=2+3=5
considering triangleAOC
AO
[tex] {ao}^{2} = {ac}^{2} + {oc}^{2} [/tex]
[tex] {5}^{2} = {3}^{2} + {ac}^{2} [/tex]
[tex] {ac}^{2} = {5}^{2} - {3}^{2} [/tex]
[tex]ac = 4[/tex]