# Understand the problem

Ptolemy’s Theorem gives a relation between product of diagonals of a quadrilateral with the sum of the product of its opposite sides. However it can be proved using tools from inversive geometry (that Ptolemy probably did not know). Try this!Â

# Now watch the discussion video

#### Kazi Abu Rousan

Cheenta Creative Team

# Tutorial Problems… try these after watching the video.

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## One reply on “Inversion and Ptolemy’s Theorem”

Impressive Demonstration!

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