In Fig, ∠ ABC = 69°, ∠ ACB = 31°, find ∠ BDC.
In Fig, ∠ ABC = 69°, ∠ ACB = 31°, find ∠ BDC.
Solution and Explanation
ΔABC,
∠ABC = ∠ACB + ∠BAC = 180° 6
9 + 31 + ∠BAC = 180
100 + ∠BAC = 180
∠BAC = 180 – 100
∠BAC = 80°
∠BAC and ∠BDC are angles in same segment. These are equal.
∠BDC = ∠BAC = 80°
∴ ∠BDC = 80°
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