Try to solve the equation. Move point C to get new examples.
Maybe the cathetus theorem can help you.
Geocentrism and Heliocentrism
The Area of a Regular Triangle and The Ratio its Radii
Angle Pairs formed by 2 intersecting lines. Vertical Angles
[Quantum Continuum]: Lemma - Bijective Square The Circle - Infinite Precision [graphical method]
Trigonometric ratios for some specific angles
Domain & Range: Illustrated v3
Vivek_Circles and Rectangles