Pick any point on a conic section, and draw a series of right angles having this point as their vertices. Then the line segments connecting the rays of the right angles where they intersect the conic section concur in a point , as illustrated above.

# Frégier's Theorem

## See also

Conic Section, Right Angle## Explore with Wolfram|Alpha

## References

Wells, D.*The Penguin Dictionary of Curious and Interesting Geometry.*Middlesex, England: Penguin Books, p. 83, 1991.

## Referenced on Wolfram|Alpha

Frégier's Theorem## Cite this as:

Weisstein, Eric W. "Frégier's Theorem."
From *MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/FregiersTheorem.html