A line of symmetry divides a figure into two congruent parts, each of which is the mirror image of the other. Lines of symmetry are not limited to horizontal and vertical lines.
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The symbol ~ is used to represent similarity.
How do polygons that are similar compare to polygons that are congruent? Congruent polygons have the same size and shape. Similar polygons have the same shape, and corresponding angles between the similar figures are congruent. However, the lengths of the corresponding sides are proportional. All congruent polygons are considered similar with the ratio of the corresponding sides being 1:1.
Identify corresponding sides and corresponding and congruent angles of similar figures using the traditional notation of curved lines for the angles.
Determine if quadrilaterals or triangles are similar by examining congruence of corresponding angles and proportionality of corresponding sides.
Given two similar figures, write similarity statements using symbols such as △ABC is congruent to △DEF, ∠A corresponds to ∠D, and line segment AB corresponds to line segment DE.