In ΔABC, ∠A = 50° and the external bisectors of ∠B and ∠C meet at O as shown in figure. The measure of ∠BOC is

Answer:
17
Step-by-step explanation:
Look at Triangle ABC, The rays meet at line BC and they are both from the interior point A. So this means that AB=AC. This makes ABC a isosceles triangle. Using the isosceles triangle theorem, Angle B and Angle C measure is equal to each other so
[tex]50 + x + x = 180[/tex]
[tex]50 + 2x = 180[/tex]
[tex]2x = 130[/tex]
[tex]x = 65[/tex]
This means angle b and C of the triangle ABC measure is 65.
External bisector bisect a figure that it makes the original angle split into half that they are equal to each other.
This means the angle below Angle B and angle C measure is 32.5. We can find the measure of Angle B and C in triangle BOC. This is a isosceles triangle as well so
[tex]32.5 + 65 + x = 180[/tex]
[tex]98.5 + x = 180[/tex]
[tex]x = 81.5[/tex]
Angle C is 81.5 as well so
[tex]81.5 + 81.5 = 163[/tex]
Find angle o
[tex]180 - 163 = 17[/tex]