Part 1: Use the protractor to measure angles 1 and 2 below.
What did you get for the measure of [math]\angle1[/math]? How about [math]\angle2[/math]?
Use the slider above to change the size of the angles. Measure angle 1 and angle 2. What did you get?
Part 2: Use the slider below to change the sizes of angles 1 and 2. Use the protractor to measure them both again.
[math]\angle1[/math] and [math]\angle2[/math] are said to be [i]vertical [/i]angles. From your observations, what seems to be true about vertical angles?