New posts in Triangles

In $\Delta ABC, AC > AB.$ The internal angle bisector of $\angle A$ meets $BC$ at $D,$ and $E$ is the foot of the perpendicular from $B$ onto $AD$.

Point $M$ lies inside $\triangle ABC$, $\angle MAC = 10^\circ$ and $\angle MCA = 30^\circ$. Find $(180^\circ - \angle BMC)$

$4$ points in order $A,B,C,D$ lie on a circle with the extension of $AB$ meeting the extension of $DC$ at $E$ and that of $AD$ and $BC$ at $F$.

Can a triangle be divided into four similar triangles such that not all four of the triangles are congruent to each other?

Six points on an ellipse: generalizing Conway's Circle Theorem

Area of sub-triangle inside a triangle

A generalization of Bottema's theorem

Can a triangle ABC be made if $\frac{\cos A}{2}=\frac{\cos B}{3}=\frac{\cos C}{7}$

Proof of relationship $S^2−S(a+b+c+d+e)+ab+bc+cd+de+ea=0$ between areas connected to a pentagon

Radius of the circumscribed circle of an isosceles triangle