Question

please answer with procedure and reasons.

Answer 1

In the ∆ABC
angle A + angle B + angle C = 180
70 + angle B + angle C = 180
angle B + angle C = 110
Now,Angle C + Angle BCD = 180
Angle BCD = 180 - Angle C
Angle B + Angle CBE = 180
Angle CBE = 180 - Angle B
Then,according to your question =>
Angle BCD/2 + Angle CBE/2 + Angle O = 180 (here substitute the values)
(180 - Angle C)/2 + (180 - Angle B)/2 + Angle O = 180
(180 - Angle C + 180 - Angle B)/2 + Angle O= 180
(360 - Angle C - Angle B)/2 + Angle O = 180
{360 - (Angle B + Angle C)}/2 + Angle O = 180 (We know that Angle B + Angle C = 110 from our previous equations)
{360 - (110)}/2 + Angle O = 180
250/2 + Angle O = 180
125 + Angle O = 180
Angle O = 180 - 125 = 55° is your solution.

Answer 2

Hlo friend
________________________________

Here is ur answer :
Please see the attached picture..
After the picture

☣️1/2(360 - 110) + /_ BOC = 180

☣️1/2 (250) + BOC = 180

☣️125 + BOC = 180

☣️BOC = 180- 125

☣️BOC = 55

HOPE IT HELPS YOU.. PLS MARK ME AS BRAINLIEST...

REGARDS
@SUNITA