10-20-30-40 What Comes Next
Geometry
Level
4
In triangle \(ABC\), we have a point \(D\) such that \( \angle DAC = 10^\circ\), \(\angle DCA = 20^\circ\), \(\angle DAB = 30^\circ\) and \(\angle ABC = 40^\circ\). What is \( \angle BDC\)?
by
Calvin Lin