Question 40
Let $ABC$ be a triangle with $AC \gt AB$ and circumcenter $O$. The tangents to the circumcircle at $A$ and $B$ intersect at $T$. The perpendicular bisector of the side $BC$ intersects $AC$ at $S$.
a. Prove that the points $A$, $B$, $O$, $S$ and $T$ lie on a common circle.
b. Prove that the line $ST$ is parallel to the side $BC$.
a. Prove that the points $A$, $B$, $O$, $S$ and $T$ lie on a common circle.
b. Prove that the line $ST$ is parallel to the side $BC$.