Van Aubel's theorem states that if you start with a convex quadrilateral and construct a square on each side, externally to the quadrilateral, then the line segments connecting the centers of opposite squares will be equal in length and perpendicular to each other.

#math
#geometry
#illustration

As one who studied Euclidean #geometry in college, I sometimes have trouble engaging too deeply sacred geometry, but that star figure on the top left actually has some really nice properties around basic fractions. At a party, I once had someone ask me if sacred geometry was a non-Euclidean geometry. Fair question. I wonder what the cat thinks.

This piece is #watercolor, ink, and mica watercolor on paper. The bronze knot shimmers on the light. #MathArt