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Roaming Rhombus

Stage: 4 Challenge Level: Challenge Level:1

Created with GeoGebra

Four rods of equal lengths are hinged at their endpoints to form a rhombus ABCD.

Keeping AB fixed, CD is free to move in the plane with the angle BAD between 0 and 180 degrees.

What is the locus (or path) of the point D?

What is the locus of Y, the point one third of the way along DC? (DY:YC = 1:2)

NOTES AND BACKGROUND

You might like to download your own free copy of GeoGebra from the link above and draw this dynamic diagram for yourself. You will find it easy to get started on GeoGebra with the Quickstart guide for beginners.