Back to Unit 18
Similar and Congruent Shapes
Congruent figures have
the same shape and are the exact same size.
shapes are also similar.
Similar figures have the same shape, but not necessarily the
- The corresponding sides of similar figures are in
proportion. In other words
if a small triangle is similar to a larger triangle, if the corresponding
side of the large triangle is double the corresponding side of the small
triangle, all the sides of the large triangle will be double the smaller
- The corresponding angles of similar figures are
- The symbol ~ means similar.
- When you identify two polygons as similar, you
must name their corresponding vertices in the same order. For
example abc~ xyz means that <a corresponds to
<x and <b corresponds to
<y and <c corresponds to <z
To check if two figures are
similar, find two sets of corresponding sides and create a proportion.