Question

Find angle BOC in the given figure if AOB = 30 degrees and AC is the diameter of the given circle.

Answer 1

As AC is diameter, $\angle AOC={180}^o$

$\angle AOC=\angle AOB+\angle BOC$

${180}^o={30}^o+\angle BOC$

$\angle BOC={180}^o-{30}^o={150}^o$