Textbook Problem

In Exercises 27 to 35, complete the formal proof of each theorem.

If two angles are complementary to the same angle, then these angels are congruent.

Given:	$\angle 1$ is complementary to $\angle 3$ $\angle 2$ is complementary to $\angle 3$
Prove:	$\angle 1\cong \angle 2$

PROOF
Statements	Reasons
1. $\angle 1$ is complementary to $\angle 3$ $\angle 2$ is complementary to $\angle 3$	1. ?
2. $\begin{array}{l}\text{m}\angle 1+\text{m}\angle 3=90\\ \text{m}\angle 2+\text{m}\angle 3=90\end{array}$	2. ?
3. $\begin{array}{l}\text{m}\angle 1+\text{m}\angle 3=\\ \text{m}\angle 2+\text{m}\angle 3\end{array}$	3. ?
4. $\text{m}\angle 1=\text{m}\angle 2$	4. ?
5. $\angle 1\cong \angle 2$	5. ?