Q. 194.5( 4 Votes )
In Fig. 6.9, BC = CA and ∠A = 40. Then, ∠ACD is equal to

A. 40°
B. 80°
C. 120°
D. 60°
Answer :
Exterior angle is equal to sum of opposite interior angles
∠ACD = ∠A + ∠B
As ΔACB is isosceles triangle with AC = BC
Then ∠A must be equal to ∠B
∴ ∠ACD = 40° + 40° = 80°
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