Similar Figures Notes

Solving Proportions Review

Before we can discuss Similar Figures we need to review how to solve proportions…. Any ideas?

Solving Proportions

Solving Proportions: You must cross multiply and solve for the missing value.

2 5

= x 35

2(35) = 5x70 = 5x____

5____

5x = 14

Proportions Practice x = 14 r = 28 k = 45 z = 9 d = 66 s = 72 w = 36 t = 12

a = 24 f = 14 h = 18 c =135 z = 60 k = 16 n = 15

Similar Figures (~)

Similar Figures

Similar Figures: have the same shape but are not the same size.

Corresponding Angles of Similar Figures: are congruent.

Corresponding Sides of Similar Figures: are in proportion.

Naming Similar Figures When naming similar figures,

list the corresponding sides and the angles in the same order. For example, ∆ABC ~ ∆DEFCorresponding

Angles

<A & <D <A & <D <A & <D

CorrespondingSides

AB & DE BC & EF AC & DF

Similar Figures (~)

Two Figures are Similar if: Corresponding angles are congruent Corresponding sides are in proportion

82◦

Corresponding angles

D

E

F

Corresponding sides

A

B

C

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55◦43◦ 55◦43◦