In $$\triangle$$ABC, D is a point on BC such that $$\angle$$BAD = $$\frac{1}{2} \angle$$ADC and $$\angle$$BAC = 77$$^\circ$$ and $$\angle$$C = 45$$^\circ$$. What is the measure of $$\angle$$ADB?
$$\angle$$ADC = x
Given, $$\angle$$BAD = $$\frac{1}{2} \angle$$ADC
$$\angle$$BAD = $$\frac{\text{x}}{2}$$
$$\angle$$DAC = 77 -Â $$\frac{\text{x}}{2}$$
From triangle ADC,
$$\angle$$ADC +Â $$\angle$$ACD +Â $$\angle$$DAC = 180$$^\circ$$
x +Â 45$$^\circ$$ + 77 -Â $$\frac{\text{x}}{2}$$ =Â 180$$^\circ$$
$$\frac{\text{x}}{2}$$ = 58$$^\circ$$
x =Â 116$$^\circ$$
$$\angle$$ADB =Â 180$$^\circ$$ - x
=Â 180$$^\circ$$ -Â 116$$^\circ$$
= 64$$^\circ$$
Hence, the correct answer is Option B
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