POINT • CIRCLE • CIRCLE
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Two Tangent Circles Of The Same Size, Point On The Circle
Number of solutions: 1
GeoGebra construction
Steps
- point A is chosen as the centre of a circle inversion, the radius of the circle is chosen to intersect both of the given circles, we construct circle k
- we display circles k1 and k2 in a circle inversion, circle k1' and line k2' are created
- in the point of tangency of k1' and k2' is located point C, we run circle o to line k2' passing through point C
- In the point of intersection of k1', point C is found
- we create a parallel line k4' to line k2 passing through point C
- we display line k4' in a circle inversion through circle k, the final circle is the solution of the problem
GeoGebra construction
Steps
- We draw lines passing through point A and the centers of the given circles, i.e., points C and B.
- We mark the intersections of the line with the circle that does not contain point A from the given conditions. In this case, it is circle b.
- We find the midpoints between the intersections F, E, and point A, which will then lie on the sought hyperbolas.
- Using two foci and a point lying on the hyperbola, we construct the hyperbola. We choose points A and B as the foci, and one of the midpoints G or H as the point lying on the hyperbola.
- For the center of circle C and point A, there already exists a set of points in the form of line g. It intersects with the hyperbola at two points: point C and a new intersection, which we label as S.
- We draw the final circle k around center S. Point C is already the center of circle c, which follows from the given conditions and is therefore not a solution.
- The problem has a unique solution.