In Fig. 8.61, lines AB, CD and EF intersect at O. Find the measures of AOC, COF, DOE and BOF.

AOE + EOB = 180o(Linear pair)

AOE + DOE + BOD = 180o


DOE = 105o


DOE = COF = 105o(Vertically opposite angle)


AOE + AOF = 180o(Linear pair)


40o + AOC + 105o= 180o


AOC = 35o


Also,


BOF = AOE = 40o(Vertically opposite angle)


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