1. Section 7.4-7.5 Review Triangle Similarity

2. Similar Triangles Triangles are similar if (1) their corresponding (matching) angles are congruent (equal) and (2) the ratio of their corresponding sides are in proportion. The name for this proportion is the scale factor. Triangles are similar if (1) their corresponding (matching) angles are congruent (equal) and (2) the ratio of their corresponding sides are in proportion. The name for this proportion is the scale factor.

3. Theorems There are three theorems that you can use to prove two triangles similar. AA Similarity SSS Similarity SAS Similarity (included angles) There are three theorems that you can use to prove two triangles similar. AA Similarity SSS Similarity SAS Similarity (included angles)

4. SSS Similarity If there is a matching such that corresponding sides in a pair of triangles are proportional, then the triangles are similar. In English - All three sides must have the same proportion (scale factor) If there is a matching such that corresponding sides in a pair of triangles are proportional, then the triangles are similar. In English - All three sides must have the same proportion (scale factor)

5. SAS Similarity If a pair of matching sides in a pair of triangles have proportional lengths and their included angles are equal then the pair of triangles are similar. Look for --> Proportion, Equal, Proportion If a pair of matching sides in a pair of triangles have proportional lengths and their included angles are equal then the pair of triangles are similar. Look for --> Proportion, Equal, Proportion

6. AA Similarity Triangles are similar if the measures of two interior angles in one triangle are equal to the corresponding angles in another triangle. Why just two? If you know two angles the third angle is not negotiable. Triangles are similar if the measures of two interior angles in one triangle are equal to the corresponding angles in another triangle. Why just two? If you know two angles the third angle is not negotiable.