To investigate: Click and drag the vertices of the triangle.[br][br]Complete the following steps/questions.[br][br]Click and drag the vertices forming an acute triangle.[br]Record the interior angle measures of the triangle.[br]1) Write a general equation relating the interior angle measure.[br]2) Repeat above steps/question for a right triangle.[br]3) Repeat above steps/question for an obtuse triangle.[br]4) What do you observe about the triangle's 3 interior angles?[br]Rotate the triangle 180 degrees about midpoint of AC and AB, by moving the sliders to 180.[br]5) What do you observe?[br]6) How does the rotation of the triangles relate to the triangle sum?[br]7) Does what you observed hold true for each case? Why or why not?

Investigating the Exterior Angles of a Triangle.[br][br]1. Drag any of the vertices of the triangle around on the screen. What do you observe about the interior angles?[br]2. Create acute, obtuse and right triangle?[br]3. Record the measurements of the adjacent angles at point C.[br]4. What do you observe about the adjacent angles at point C?[br]5. Write a general equation about the adjacent angles at point C.[br]6. Record the measurements of marked exterior angle and the other interior angles.[br]7. What do you notice the relationship with the marked exterior angle and the other interior angles?[br]8. Write a general equation about the marked exterior angle and the other interior angles.