In ΔABC, AC = BC and ∠ABC = 50°, the side BC is produced to D so that BC = CD then the value of ∠BAD is:
A. 80°
B. 40°
C. 90°
D. 50°
Answer: Option C
Solution (By Examveda Team)

In ΔABC
∠B = ∠A = 50°
∠ACD = 50° + 50°
∠ACD = 100°
∠ACD is the external angle or ΔABC
∠ACD + ∠CAD + ∠ADC = 180°
∠CAD = ∠ADC
∵ AC = CD
2∠CAD = 180 - 100
∠CAD = 40°
∠BAD = 50° + 40°
∠BAD = 90°



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