Hi,
Forgot how to do this.
The line y = -1 is a tangent to a circle which passes through (0, 0) and (6, 0).
Find the equation of the circle.
Any help appreciated
Well the circle equation is
So putting the two points in gives
and
The circle is tangent to the line y = -1. This tells us a few things. First, the circle has a point (X, -1) on it:
We also know that the derivative of the circle equation is 0 at y = -1, since y = -1 is a horizontal line. So taking the derivative of the circle equation we get
The derivative at (X, -1) is 0, so this becomes
Thus you need to solve the system of equations:
-Dan