Answer:
∠ BCD = 111°
Step-by-step explanation:
Since AB = BC then the triangle is isosceles and the 2 base angles are congruent.
∠ ACB = ∠ A = 69°
∠ ACB and ∠ BCD are adjacent angles and sum to 180° , that is
∠ BCD + ∠ ACB = 180°
∠ BCD + 69° = 180° ( subtract 69° from both sides )
∠ BCD = 111°
