



 
Hi Trent, I would first draw a diagram. I added three line segments to form a right triangle. Use either the distance formula or Pythagoras Theorem to find the distance $r$ between the two points. Since one point is the center of the circle and the other is on the circle $r$ is the radius of the circle. Let $(x, y)$ be some point in the plane. $(x, y)$ is on the circle if and only if the distance from $(2, 3)$ to $(x, y)$ is $r.$ Use the distance formula to find the distance from and set it equal to $r$ to form an equation. Square both sides and simplify. Penny  


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