OA = OC = radius OE ⊥ AB OF ⊥ CD ∴ AE = EB = 5 cm. CF = FD = 2 cm. OE = x cm. In ΔOAE, OA2=AE2+OE2 ⇒OA2=52+x2.....(i) In ΔOCF, OC2=22+(x+3)2.....(ii) ∴52+x2=22+(x+3)2 ⇒25+x2=4+x2+6x+9 ⇒6x=25−13=12 ⇒x=
12
6
=2cm ∴OA2=25+x2=25+4=29 ∴OA=√29cm. ∴ Diameter of circle =2√29cm