Two triangles are similar if and only if the corresponding sides are in proportion and the corresponding angles are congruent. Just as there are specific methods for proving triangles congruent (SSS, ASA, SAS, AAS and HL), there are also specific methods that will prove triangles similar.Click to see full answer. Furthermore, what are the 3 ways to prove triangles are similar? Triangles are similar if: AAA (angle angle angle) All three pairs of corresponding angles are the same. SSS in same proportion (side side side) All three pairs of corresponding sides are in the same proportion. SAS (side angle side) Two pairs of sides in the same proportion and the included angle equal. Furthermore, how many similarity theorems are there? four theorems In respect to this, what are the triangle similarity theorems? There are three triangle similarity theorems that specify under which conditions triangles are similar: If two of the angles are the same, the third angle is the same and the triangles are similar. If two sides are in the same proportions and the included angle is the same, the triangles are similar.How do you know if triangles are congruent?If two angles and the non-included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent.