MathDB

9.3

Part of 2009 Moldova National Olympiad

Problems(1)

AC // BK wanted, equilaterals ABC and MKC

Source: 2009 Moldova NMO 9.3

3/27/2021
Let ABCABC be an equilateral triangle. The points MM and KK are located in different half-planes with respect to line BCBC, so that the point M∈(AB)M \in (AB) ¸and the triangle MKCMKC is equilateral. Prove that the lines ACAC and BKBK are parallel.
geometryEquilateralparallel