Blanchet's theorem | plane geometry | intermediate level

Episode 76.

Blanchet's theorem | plane geometry | intermediate level.

Branch of mathematics: plane geometry.
Difficulty level: intermediate.

Theorem. Let $ABC$ be a triangle and let $BH_B$ be the altitude in this triangle. Let $X$ be an arbitrary point on the altitude $BH_B$. Let $D$ be the intersection point of $CX$ and $AB$. Let $E$ be the intersection point of $AX$ and $BC$. Then $H_BB$ is the bisector of the angle $DH_BE$ (in other words, $\angle{DH_BB}=\angle{EH_BB}$).

Mathematics. Geometry. Plane geometry.
#Mathematics #Geometry #PlaneGeometry

The same video on YouTube:
https://youtu.be/3H0DfsFqVOw

The same video on Telegram:
https://t.me/mathematical_bunker/100