Chapter 2.2, Problem 11WE

To determine

To prove: $m\angle SRT=m\angle STR$ using two column method.

Explanation of Solution

Given:

The given figure is,

  

And the conditions are,

  $m\angle 1=m\angle 2\text{and }m\angle 3=m\angle 4$

Statement	Reason
$m\angle 1=m\angle 2\text{and }m\angle 3=m\angle 4$	Given
$m\angle 1+m\angle 3=m\angle 2+m\angle 3$	Adding both equation   $m\angle 1=m\angle 2\text{and }m\angle 3=m\angle 4$
$m\angle SRT=m\angle STR$	From the figure,   $m\angle 1+m\angle 3=m\angle SRT$ and $m\angle 2+m\angle 3=m\angle STR$