Problem
1. $\triangle A B C \cong \boldsymbol{D E F}$. Find the length of $C \overline{A, D E, E F}$. Find the angle measure of $\angle A, \angle B, \angle C$. Since $\triangle A B C \cong \triangle D E F$, these six facts are always true. Corresponding sides are congruent $\quad$ Corresponding angles are congruent The side lengths are as follows: The angle measures are as follows: \[ \begin{array}{l} C A=3.5 \mathrm{~cm} \\ -D E=2.6 \mathrm{~cm} \\ E F=3.7 \mathrm{~cm} \end{array} \] \[ \begin{array}{l} m \angle A=73^{\circ} \\ m \angle B=65^{\circ} \\ m \angle C=42^{\circ} \end{array} \]
Solution
Step 1 ：Since the triangles $\triangle ABC$ and $\triangle DEF$ are congruent, their corresponding sides and angles are equal.
Step 2 ：Therefore, the length of $\overline{CAD}$ is equal to the length of $\overline{CA}$, which is 3.5 cm.
Step 3 ：Similarly, the measures of $\angle A$, $\angle B$, and $\angle C$ are equal to the measures of $\angle D$, $\angle E$, and $\angle F$ respectively, which are $73^\circ$, $65^\circ$, and $42^\circ$.
Step 4 ：So, the length of $\overline{CAD}$ is \(\boxed{3.5}\) cm and the measures of $\angle A$, $\angle B$, and $\angle C$ are \(\boxed{73^\circ}\), \(\boxed{65^\circ}\), and \(\boxed{42^\circ}\) respectively.
