If \( BD \) bisects \( \angle ABC \), it means that \( \angle ABD \) and \( \angle DBC \) are equal.
Given that \( m\angle BDC = 33^\circ \), we can use the fact that the angles around point \( B \) add up to \( 180^\circ \):
\[ m\angle ABC + m\angle BDC = 180^\circ \]
Since \( m\angle ABC \) is composed of \( \angle ABD + \angle DBC \), and each of those is half of \( m\angle ABC \) (because \( BD \) bisects it), we can express the relationship as follows:
Let \( m\angle ABC = x \). Then:
\[ x + 33^\circ = 180^\circ \]
Solving for \( x \):
\[ x = 180^\circ - 33^\circ \] \[ x = 147^\circ \]
Thus, \( m\angle ABC = 147^\circ \).