must do more algebra

by math_explorer, Jan 27, 2011, 11:13 PM

later.

One-liner:
Induct on the statement "if a part can be removed, it must lie within a triangle ABC where A, B, C are consecutive vertices". QED

So random clicks brought me to this problem from the Lithuania National Olympiad.
Two circles are tangent externally at a point $B$. A line tangent to one of the circles at a point $A$ intersects the other circle at points $C$ and $D$. Show that $A$ is equidistant to the lines $BC$ and $BD$.

(by the way "externally" was missing an L)
geo problem
geometry
one-liner

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