2019 AMC 12A Problem 22
Problem 22 of 25HarderGeometry
Circles and both centered at have radii and respectively. Equilateral triangle whose interior lies in the interior of but in the exterior of has vertex on and the line containing side is tangent to Segments and intersect at and Then can be written in the form for positive integers with What is
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Solution
Let Since we have and Put at the origin with on the -axis, and apex
Points are collinear, so for some scalar Two conditions pin it down: is at distance from line giving and is on giving since
Solving, and The valid configuration has and on opposite sides of so Therefore
Then
Thus, the correct answer is E.