Q5 of 69 Page 9

Side BC of a triangle ABC has been produced to a point D such that ∠ACD = 120°. If ∠B = ∠A, then ∠A is equal to

By exterior angle theorem:

∠ACD = ∠A + ∠B


120o = ∠A + ∠A


120o =


240o = 3∠A


∠A = 80o

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