1. SIMILAR POLYGONS Two figures are similar if
Corresponding ANGLES are CONGRUENT
Corresponding SIDES are PROPORTIONAL

3. Solve each proportion:

4. DON’T FORGET –

5. Example:
Determine whether the pair of triangles is similar.
Justify your answer. Show all work.

6. Scale Factor If the Scale Factor < 1 polygon is getting smaller
The ratio of the lengths of two corresponding sides of two similar polygons or two similar solids
NOTE: The scale factor for two similar polygons depends on the order of comparison
If the Scale Factor < polygon is getting smaller
If the Scale Factor > polygon is getting bigger
If the Scale Factor < polygon is getting smaller
If the Scale Factor > polygon is getting bigger
Reduction k<1
Enlargement k>1

7. Always, Sometimes or Never
Congruent triangles are __________similar.
Similar triangles are __________ congruent.
Equiangular octagons are __________ similar.  
Always, Sometimes or Never