fundamental theorem of similarity
mathematics
Also known as: proportional segments theorem
Quick Summary
Fundamental theorem of similarity
The formula in this diagram reads k is to l as m is to n if and only if line DE is parallel to line AB. This theorem then enables one to show that the small and large triangles are similar.
The fundamental theorem of similarity, also known as the proportional segments theorem, states that a line segment drawn through a triangle, parallel to one of its sides, divides the other two sides proportionally[1
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