In ∆ABC , ∠B = 60° , and ∠C = 40°

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In ∆ABC , ∠B = 60° , and ∠C = 40° , AD and AE are respectively the bisector of ∠A and perpendicular on BC. The measure of ∠EAD is :

1. 11°
2. 10°
3. 12°
4. 9°

Correct Option: B

As per the given in question , we draw a figure triangle ABC

∠B + ∠C = 60° + 40° = 100°
∴ ∠A = 180° – 100° = 80°
∴ ∠BAD = 40°
In ∆ ABE,
∠AEB = 90°
∴ ∠BAE = 180° – 90° – 60° = 30°
∴ ∠EAD = ∠BAD – ∠BAE = 40° – 30° = 10°