Two triangles are similar if their triples of vertex angles are the same.
Similar Triangles
See also
Directly Similar, Inversely Similar, Similar, SimilarityExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Similar Triangles." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/SimilarTriangles.html