2012 AMC 10A Problems/Problem 11
Contents
[hide]Problem
Externally tangent circles with centers at points and have radii of lengths and , respectively. A line externally tangent to both circles intersects ray at point . What is ?
Solution
Let and be the points of tangency on circles and with line . . Also, let . As and are right angles (a radius is perpendicular to a tangent line at the point of tangency) and both triangles share , . From this we can get a proportion.
Video Solution
https://youtu.be/NsQbhYfGh1Q?t=758
~ pi_is_3.14
See Also
2012 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 10 |
Followed by Problem 12 | |
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All AMC 10 Problems and Solutions |
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