examday

/TMUA

Let $O$ be the center of a circle, and $M$ be a point outside the circle. Two tangents are drawn from $M$ to the circle $O$, touching the circle at points $A$ and $B$. The line segment $AB$ is connected, and $MO$ intersects $AB$ at point $P$. It is given that $OP=y$, $OM=10y$ and $AB=2y+6$.

Find the area of the $S_{OBMA}$.