Given:
[tex]\angle C=19[/tex]If AB=AD then
[tex]\angle ABD=\angle\text{ADB}[/tex]And BD=CD
then:
[tex]\begin{gathered} \angle BCD=\angle DBC \\ \angle C=19 \\ \angle DBC=\angle BCD=190 \end{gathered}[/tex]So:
[tex]\begin{gathered} \angle DBC+\angle BCD+\angle CDB=180 \\ \angle CDB=180-(19+19) \end{gathered}[/tex]From straight line :
[tex]\begin{gathered} \angle CDB+\angle ADB=180 \\ 180-(19+19)+\angle ADB=180 \\ \angle ADB=19+19 \\ =38 \end{gathered}[/tex]and
[tex]\begin{gathered} \angle ADB=\angle ABD \\ \angle ABD=38 \end{gathered}[/tex]For traingle:
[tex]\begin{gathered} \angle DAB+\angle ABD+\angle ADB=180 \\ \angle DAB+38+38=180 \\ \angle DAB=180-(38+38) \\ =180-76 \\ =104 \end{gathered}[/tex]