corresponding angles are congruent
or
corresponding sides are proportional
or
corresponding sides are proportional
Method 1: Angle-Angle Similarity (AA)
To prove two triangles are similar using the AA method, you need to show that two corresponding angles of the triangles are congruent. If two angles in one triangle are congruent to two angles in another triangle, then the triangles are similar.
Method 2: Side-Angle-Side (SAS) Similarity
To prove two triangles are similar using the SAS method, you need to show that the ratio of the lengths of the corresponding sides is equal and that the included angles between the pairs of sides are congruent.
Method 3: Side-Side-Side (SSS) Similarity
To prove two triangles are similar using the SSS method, you need to show that the ratio of the lengths of all three pairs of corresponding sides is equal.
Method 4: Side-Side-Angle (SSA) Similarity
To prove two triangles are similar using the SSA method, you need to show that two corresponding sides are proportional and the angle formed between these sides is congruent in both triangles. However, SSA similarity is not a reliable method on its own, as two triangles with the same side lengths and a congruent angle may not necessarily be similar.
It is important to note that if any of these methods fail to prove the triangles similar, it does not necessarily mean they are not similar. Additional information or other methods might be required for a conclusive proof.