Chapter 12.3, Problem 16E

To determine

To prove:

The triangles $\Delta ABC\cong \Delta CDA$ are congruent using the congruence theoem.

Explanation of Solution

Given:

  $\begin{array}{l}\overline{AB}\cong \overline{CD}\\ \overline{AB}\left|\right|\overline{CD}\end{array}$

Concept used:

Two geometric figures are congruent if a rigid motion or a composition of rigid motions maps one of the figures onto other.

Calculation:

If two triangles are congruent.

So all the corresponding parts are congruent.

If all corresponding parts of two triangles are congruent.

So the triangle are congruent.

Two pairs of corresponding sides of the included angles of those sides are marked congruent.

By the reflexive property of congruence

  $\overline{AC}\cong \overline{AC}$

An angle bisect cuts an angle into two congruent

  $\begin{array}{l}\angle 1\cong \angle 2\\ \Delta ABC\cong \Delta CDA\end{array}$

So, the congruence theorem can be used.