170 likes | 447 Views
Section 8.3 Similar Polygons. Similar Figures. Two figures that have the same shape are similar Not necessarily the same size! Enlarging and shrinking. Real life example of Similarity. Similar Polygons. Two polygons are similar if: corresponding angles have the same measure
E N D
Similar Figures • Two figures that have the same shape are similar • Not necessarily the same size! • Enlarging and shrinking
Similar Polygons • Two polygons are similar if: • corresponding angles have the same measure • corresponding sides are in proportion • Symbolic notation for similarity: ~
Congruence Similarity Figures are the exact same size and shape Corresponding sides are equal Corresponding angles are equal Figures have the same shape but not necessarily the same size. Corresponding sides are in proportion Corresponding angles are equal Similarities Both have corresponding angles that are equal. Same shape of the object Both have a symbolic notation
Example of Similar Polygons Similarity Statement ABCD ~ EFGH Statement of Proportionality ________ = _________ =__________=_________
How to determine similarity: • Are corresponding angles equal? • Are corresponding sides in proportion? • Are the ratios the same?
Scale Factor • Ratio of the lengths of two corresponding sides of similar figures. • Corresponding sides change by the same scale factor. • What does this mean?
It means that all the sides of the small figure are multiplied by the same number to obtain the lengths of the corresponding sides of the large figure.