title: Put arrow head on path where intersects with a circle
body: <p>I have a path that ends at the center of a circle. I want to place an arrow head on the path pointing toward the circle. I want the point of the arrow head to be at the point of intersection between the path and the circle. How can I achieve this? </p>
  
  <p>I know the radius of the circle.  The path is a quadratic curve between two points from this accepted answer: <a href="https://stackoverflow.com/questions/31804392/create-svg-arcs-between-two-points">Create svg arcs between two points</a></p>