Instructional Video
Khan Academy

Khan Academy: Geometry: Triangle Medians and Centroids

9th - 10th
This video tutorial [8:59] reviews the definitions of median and centroid in relation to a triangle and proves that the centroid is two-thirds the way along a median. The proof is done be drawing a triangle in three-dimensions.
Instructional Video
Khan Academy

Khan Academy: Geometry: Median Centroid Right Triangle Example

9th - 10th Standards
This video tutorial [9:00]explains how to find various measures of triangles formed by the medians of a right triangle. Based on the properties of the medians of a triangle, properties of centroids, and the Pythagorean theorem.
Instructional Video
Khan Academy

Khan Academy: Triangles: Proving That the Centroid Is 2 3 Rds Along the Median

9th - 10th
This video demonstrates that the centroid divides each median into segments with a 2:1 ratio (or that the centroid is 2/3 along the median).
Instructional Video
Khan Academy

Khan Academy: Triangles: Euler Line

9th - 10th
A video demonstration of the magic and mystery of the Euler Line.
Instructional Video
Khan Academy

Khan Academy: Triangles: Median Centroid Right Triangle Example

9th - 10th Standards
This video demonstrates how to find various measures of triangles formed by the medians of a right triangle.
Instructional Video
Khan Academy

Khan Academy: Triangles: Review of Triangle Properties

9th - 10th Standards
Provides a review of perpendicular bisectors, angle bisectors, medians, and altitudes and the special points of concurrency formed by these parts of a triangle.
Instructional Video
Khan Academy

Khan Academy: Triangles: Medians Divide Into Smaller Triangles of Equal Area

9th - 10th Standards
Showing that the three medians of a triangle divide it into six smaller triangles of equal area. Also a brief discussion of the centroid is given.
Instructional Video
Khan Academy

Khan Academy: Geometry: Euler's Line Proof

9th - 10th Standards
Proves that the circumcenter, orthocenter, and centroid all lie on the same line, the Euler line. Proof relies on understanding of properties of similar triangles and properties of special parts of a triangle. [9:50]
Instructional Video
Crash Course

Crash Course Statistics #37: Unsupervised Machine Learning

9th - 10th
Unsupervised Machine Learning have not true categories to compare in order to predict a future outcome. Therefore, two types of clustering are applied: K-Means and Hierarchical clustering. Centroid, Silhouette Score, Agglomerative...