home interactive  geometry is this a square?
>>> Introduction | What is a square? | Reframe | Quadrilaterals | Conclusion
Further work
Given 4 points A, B, C and D you can always construct a square so that each point is on each side. This shows how to do it.

This display was produced by CabriJava

Have a go at making this construction yourself.

Please enable Java for an interactive construction (with Cinderella). Please enable Java for an interactive construction (with Cinderella).
Please enable Java for an interactive construction (with Cinderella).

Part of geometry