Consider the quadrilateral ABCD below, where AC = CD, angle BAD measures 73 degrees, angle ADB measures 34 degrees, and angle CBD measures 30 degrees. Using elementary geometry (Euclid's Elements), determine the measurement of angle BDC.
Unknown angle sought,
Congruence and given clues,
Quadrilateral.
With measures known well,
Including thirty degree,
Solve the puzzle's spell.
