Pavan kumar
Last Activity: 15 Years ago
(D) orthocentre
OD is the vertical pole.
Hence <DOA = <DOB = 90
It is given that <OAD = <OBD
OD is common to both triangle AOD and BOD
Hence triangles AOD and BOD are congruent.
Therefore OA = OB.
Similarly, OA = OC.
Therefore o is equidistant from A,B and C, and hence is at the orthocentre.