Chapter 1, Problem 19PT

To determine

To determine which of the option is true

Answer to Problem 19PT

D all of the above

Explanation of Solution

Given information:

  $m\angle 1=m\angle 2$

Considering option A

  $\angle 2\cong \angle 4$

This statement is true as the angles are vertically opposite angles

Now, considering option B

  $\angle 2$ Is a right angle

Angle one is equal to angle two by linear pair angles

  $\angle 1=\angle 2,\angle 2=90°$

Now, considering option C

  $l\perp m$

Proved in option B

  $\angle 1=\angle 2=90°$

Therefore, this statement is also true

All the options are true

Therefore, option D is the right answer