en.wikipedia.org/wiki/Similarity_(geometry)

Two geometrical objects are called similar if they both have the same shape, or
one has the ... **Similar triangles**[edit]. In geometry two triangles, △ABC and ...

www.mathsisfun.com/geometry/triangles-similar.html

**Similar Triangles**. Two triangles are Similar if the only difference is size (and
possibly the need to turn or flip one around). These triangles are all similar:
triangles ...

www.khanacademy.org/math/geometry/hs-geo-similarity/hs-geo-triangle-similarity-intro/v/similar-triangle-basics

Sal explains what it means for **triangles** to be **similar**, and how this follows from
the definition of similarity.

www.khanacademy.org/math/geometry/hs-geo-similarity/hs-geo-solving-similar-triangles/v/similarity-example-problems

Sal solves two problems where a missing side length is found by proving that
**triangles** are **similar** and using this to find the measure.

www.khanacademy.org/math/geometry/hs-geo-similarity/hs-geo-solving-similar-triangles/e/solving_similar_triangles_1

Given two **similar triangles** and some of their side lengths, find a missing side
length.

www.mathopenref.com/similartriangles.html

Definition and properties of **similar triangles** - testing for similarity.

www.varsitytutors.com/hotmath/hotmath_help/topics/similar-triangles

Two triangles are said to be similar if their corresponding angles are congruent
and the corresponding sides are in proportion . In other words, **similar triangles** ...

mathbitsnotebook.com/Geometry/Similarity/SMNumber.html

The use of **similar triangles** appears in the solutions to many different types of
mathematical problems. The good news is that there are often several different ...