Let be an arbitrary point on the curve. It will be simpler to minimize the square of the distance between this arbitrary point and the given fixed point. Can you state the square of this distance?
We have two points:
and .
Now, the distance formula tells us the distance between the two points and is:
So, choose either of our two points to be and the other as and plug into the equivalent:
Then simplify and optimize by differentiation. Be sure to demonstrate you have minimized by using an appropriate test.