what is m<BCD
OA) 80°
OB) 90°
C) 100°
D) 110°
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Answer:
D
Step-by-step explanation:
The external angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠ BCD is an exterior angle of the triangle, thus
∠ BCD = 50° + 60 = 110° → D