This applet illustrates how Angle-Side-Side is insufficient to prove congruency by demonstrating that sometimes two triangles are formed.
Checkbox Show Sample Triangles gives suggestions for students to reform triangle ABC to observe various outcomes.
Have students make conjectures about why and when it "Angle-Side-Side" does not work.
Note: the case of 0 triangles formed is not included in this applet since we begin with an existing triangle ABC. This is intentional: it is an abstraction to work with zero triangles. In my classroom, I would bring up that case after this applet is explored fully.
