In Exercises 13 to $18,$ use only the given information to state the reason why $\triangle A B C \cong \triangle D B C .$ Redraw the figure and use marks like those used in Exercises 9 to 12 .
$$\angle 1 \text { and } \angle 2 \text { are right } \angle \mathrm{s}, \overline{A B} \equiv \overline{B D}, \text { and } \angle A \equiv \angle D$$
(GRAPH CANT COPY)