Changes

A '''triangle''' is a three-sided figure, made by any three points that are not colinear.

A '''triangle''' is a three-sided [[geometric]] [[shape]], made by any three points that are not [[collinear]].

In [[Euclidean geometry]], each side of a triangle is perfectly straight, and the sum of the internal angles of a triangle is always 180º.

In [[Euclidean geometry]], each side of a triangle is perfectly straight, and the sum of the internal angles of a triangle is always 180º.

==Congruence of triangles==

==Congruence of triangles==

Triangles can be proven [[congruence|congruent]] in the following ways:

Triangles can be proven [[congruent]] in the following ways:

'''Side-Angle-Side (SAS)''': If two sides are equal and the included angle is equal to another triangle, then the triangles are congruent.<br>

'''Side-Angle-Side (SAS)''': If two sides are equal and the included angle is equal to another triangle, then the triangles are congruent.<br>