In the given figure AB || CD and O is a point joined with B and D, as shown in the figure such that ABO = 35 and CDO = 40°. Reflex BOD = ?

Draw a line EF such that EF || AB and EF || CD crossing point O.


ABO + EOB = 180o(Sum of consecutive interior angles is 180o)


EOB = 180 – 35 = 145o


EF || AB such that AO is traversal.


CDO + EOD = 180o(Sum of consecutive interior angles is 180o)


EOD = 180 – 40 = 140o


BOD = EOB + EOD


= 145 + 140


= 285o

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