The Total solution for NCERT class 6-12
In тИЖBOC and тИЖAOD, we haveтИаBOC = тИаAODBC = AD [Given]тИаBOC = тИаAOD [Vertically opposite angles]тИ┤ тИЖOBC тЙЕ тИЖOAD [By AAS congruency]тЗТ OB =OA [By C.P.C.T.]i.e., O is the mid-point of AB.Thus, CD bisects AB.