CIRCLE • CIRCLE • CIRCLE
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One Circle Inside Another, Third Has Internal Tangency with the Outer and External Tangency with the Inner
Number of solutions: 4
GeoGebra construction
Steps
- We choose the reference circle for the inversion. Its center is chosen at the point of tangency of the given circles.
- We apply the circular inversion to the given objects. The circle passing through the point of tangency is transformed into a line.
- The first three solution circles are transformed into circles tangent to the images of the given circles. We find them using sets of points with given properties.
- The last solution circle is transformed into tangent to a circle parallel to the images of the given circles.
- We invert the images of the solution circles back using the same inversion.
- The problem has four solutions.