In the given figu

As we know that sum of adjacent angle on a straight line is 180^o.

According to question,

∠ AOC = (3x + 10)°

∠ BOC = (4x – 26)°

3x + 10 + 4x – 26 = 180^o

7x – 16 =180^o

7x =196^o

X= 28^o

∠ BOC = (4x – 26)°

∠ BOC = 112° – 26°

∠ BOC = 86°