Back to Unit 18


Similar and Congruent Shapes


Congruent figures have the same shape and are the exact same size.

        All congruent shapes are also similar.


Similar figures have the same shape, but not necessarily the same size.









To check if two figures are similar, find two sets of corresponding sides and create a proportion.

Text Box: 11m

 Text Box: y


Text Box: b


abc~ xyz

Text Box: c
Text Box: a
Text Box: 5m
Text Box: 13.2mm
Text Box: z








Text Box: Their cross products are equal (66) so these triangles are similar


Text Box: So create a proportion with the corresponding segment values:  If their cross products are equal, they are similar.