12.1. Reflection Symmetry http://www.ck12.org
Example C
Does the figure below have reflection symmetry?
Yes, this figure has reflection symmetry.
Watch this video for help with the Examples above.
MEDIA
Click image to the left for more content.CK-12 Foundation: Chapter12ReflectionSymmetryB
Concept Problem Revisited
The starfish has 5 lines of symmetry.
Vocabulary
Aline of symmetryis a line that passes through a figure such that it splits the figure into two congruent halves.
Reflection symmetryis present when a figure has one or more lines of symmetry.
Guided Practice
Find all lines of symmetry for the shapes below.
Answers:
For each figure, draw lines through the figure so that the lines perfectly cut the figure in half. Figure 1 has eight, 2
has no lines of symmetry, and 3 has one.
Practice
For #1 through #8, determine whether each statement is true or false.
- All right triangles have line symmetry.
- All isosceles triangles have line symmetry.
- Every rectangle has line symmetry.
- Every rectangle has exactly two lines of symmetry.
- Every parallelogram has line symmetry.