Triangle Similarity Theorems - Geometry Honors

AA~

If two angles of one triangle are congruent to two angles of another triangle, then the triangles are similar.

SAS~

If an angle of one triangle is congruent to an angle of a second triangle and the sides that include the two angles are proportional, then the triangles are similar.

SSS~

If the corresponding sides of two triangles are proportional, then the triangles are similar.

Cross products property

in a proportion, the product of the means equals the product of the extremes.