Let ω1 and ω2 be two different circles that intersect at two different points, X and Y. Let lines l1 and l2 be common tangent lines of these circles such that l1 is tangent ω1 at A and ω2 at C and l2 is tangent ω1 at B and ω2 at D. Let Z be the reflection of Y respect to l1 and let BC and ω1 meet at K for the second time. Let AD and ω2 meet at L for the second time. Prove that the line tangent to ω1 and passes through K and the line tangent to ω2 and passes through L meet on the line XZ. geometrygeometric transformationreflection