angle AOC = 85 degree and
angle AOC = angle AOB + angle BOC
85=4x-15 +2x+ 10
85 = 6x -5
6x = 90
![x = (90)/(6)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/us7zpth1u4p0iez70eck6qytclzx6pztjy.png)
x=15
putting the value of x in the equation of the angleAOB and angle BOC,we get:-
angle AOB = 4x-15
= 4×15-15
=60-15
angle AOB = 45 degree.
angle BOC =2x+10
= 2×15+10
= 30+10
angle BOC = 40 degree.