# Side-Side-Side: Quick Investigation

## Interact with this app below for a few minutes. Be sure to also move the LARGE POINTS (vertices) of these triangles, as well as the slider (lower left corner).

In the app above, what do you notice? What do you wonder?

Make a conjecture about the two triangles you see above.

## In the app below here, informally show how your conjecture is true.

Suppose three sides of one triangle are in proportion to three sides of another triangle. What can we conclude about the two triangles? Why can we conclude this?