APPRENTICESHIP & WORKPLACE MATHEMATICS 10 Date: Unit 6 ...

APPRENTICESHIP & WORKPLACE MATHEMATICS 10

Date:

Unit 6 – Lines, Angles, and Similar Polygons 6.4 - Similar Polygons (Part 1) Two figures are similar if they have the same shape but are different sizes. For two figures to be similar:  corresponding angles must be the same size  corresponding sides must be proportional Statement

Reason

ABC ~ DEC

AAA

AB BC AC   DE EC DC

Corresponding sides of similar figures are in proportion

Example 1: Since ABCD ~ WXYZ, determine the corresponding sides and angles.

Example 2: Josh has drawn a scale diagram of her bedroom so she can sketch different arrangements of her furniture. On her diagram, the walls have the following lengths. If the longest wall in her room is actually 12.75’, how long are the other walls? Scale Drawing:

Actual Measurements:

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PRACTICE QUESTIONS 1)

Determine the missing sides of the following similar triangles using equivalent ratios.

b) a)

c)

1) Calculate the perimeters of triangle required triangles: a) Perimeter of DEF b) Perimeter of ABC

2)

d)

The two figures shown below are similar. Find the lengths of the sides of the smaller figure. (The diagrams are not drawn to scale).

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