[b][color=#9900ff][size=200]PART I[br][/size][/color][/b]Interact with the applet there for a few minutes. Make sure to change the angles by clicking and dragging them, then use the “Slide Me!” bar to see what happens when the angles are lined up.[br][br]Then, answer the questions that follow. [br][br][i][color=#980000]Be sure to change the locations of the triangle's WHITE VERTICES each time before you drag the slider!!! [/color][/i]
When the angles were moved from the triangle to the line, did any of blue or green angles change in size?
From your observations, what is the sum of the measures of the interior angles of [i]any triangle? [/i][br]
[b][color=#9900ff][size=200]PART II[br][/size][/color][/b]Now interact with this applet. Move each vertex point to see how the equation changes.
How does this prove or disprove your answers from the example above this one?
It shows that all three angles of a triangle always add to 180 degrees.
[size=200][color=#9900ff][b]PART III[/b][/color][/size]Interact with the applet for a few minutes. Make sure to change the angles by clicking and dragging them. Then use the “Slide Me!” bar to see what happens when the angles are lined up OUTSIDE the triangle.
What does this activity show you about the exterior angle?
This activity shows that the exterior angles is equal to the sum of the two remote interior angles.