Question

29. In triangle ABC, side BC is produced top
If ABC = 40° and ACD = 120°, then A =???


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Answer 1

ACD = 120 = B + A

120 = 40 + A

120 - 40 = A

80 = A

Answer 2

Answer:

As we know that sum of all the angles in a triangle is 180°

According to the question

40°+120°+x=180°

160°+x=180°

x=180°-160°

x=20°