angle parameter space for triangles

When you click on 'hint' two white dotted lines appear. What is the equation of each of these lines? What does each equation tell you? When you click on 'another hint' a green triangle appears. What does this region represent? There are a total of four such triangular regions below the longer white dotted line. What does each of these regions represent? Are these triangular regions all congruent? How do these triangular regions relate to your understanding of the Triangle Sum Theorem? How do each of these regions relate to your understanding of the Polya Triangle Space applet? What questions could/would you ask your students based on this applet?
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