Some of the harder/hardest questions at Mathcounts can be tackled at ease using mass point geometry
so spend some time understanding it.
From Wikipedia
From AoPS
Mass Point Geometry by Tom Rike
Mass Points by Kevin An
Mass Point Geometry from Colorado Math Circle
so spend some time understanding it.
From Wikipedia
From AoPS
Mass Point Geometry by Tom Rike
Mass Points by Kevin An
Mass Point Geometry from Colorado Math Circle