Chapter 1.4, Problem 1PSA

To determine

To Prove: $\angle 1\cong \angle 2$ .

Explanation of Solution

Given:

  

  $\begin{array}{l}\angle 1\text{is a right angle}\\ \angle 2\text{is a right angle}\end{array}$

Concept Used:

Two angles are said to be congruent if they are of the same measure.

Proof:

Here, we have

  $\begin{array}{l}\angle 1\text{is a right angle}\\ \Rightarrow m\angle 1=90°\\ \angle 2\text{is a right angle}\\ \Rightarrow m\angle 2=90°\\ \therefore m\angle 1=m\angle 2=90°\\ \Rightarrow \angle 1\text{and }\angle 2\text{are of the same measure,}\text{hence they are congruent}\text{.}\\ \therefore \angle 1\cong \angle 2\end{array}$