Area of the Triangle Formed by the Intersection of Common Tangents to 3 Circles
< It is a well known theorem that the exterior common tangents to 3 circles
intersect on a line.
The intersections of the interior common tangents form the triangle PQR.
We see by dragging A B and C that the ratio of the areas of PQR and
ABC are independent of the triangle ABC formed by the centers of the circles,
but depend only on the radii of the circles.
Can you infer the relationship between this ratio and the radii of the
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