angle parameter space for triangles

When you click on [b]'hint'[/b] two white dotted lines appear. What is the equation of [br]each of these lines? What does each equation tell you?[br][br]When you click on [b]'another hint'[/b] a green triangle appears. What does this[br]region represent? There are a total of four such triangular regions below the [br]longer white dotted line. What does each of these regions represent? [br]Are these triangular regions all congruent? How do these triangular regions [br]relate to your understanding of the Triangle Sum Theorem?[color=#ff0000][color=#000000] How do each of these[br]regions relate to your understanding of the Polya Triangle Space applet?[/color][i][b][br][br]What questions could/would you ask your students based on this applet?[/b][/i][/color]
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Information: angle parameter space for triangles