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7-8. Symmetry. Warm Up. Problem of the Day. Lesson Presentation. Course 3. 7-8. Symmetry. Course 3. Warm Up 1. 360 2. 360 3. 360 4. 360 5. 360. 1 4. 1 2. 90. 180. 1 8. 3 5. 45. 216. 2 3. 240. 7-8. Symmetry. Course 3. Problem of the Day
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7-8 Symmetry Warm Up Problem of the Day Lesson Presentation Course 3
7-8 Symmetry Course 3 Warm Up 1. 360 2. 360 3. 360 4. 360 5. 360 1 4 1 2 90 180 1 8 3 5 45 216 2 3 240
7-8 Symmetry Course 3 Problem of the Day Name four plane figures that can be rotated 180° around a center point and look the same after the rotation as they did before. Possible answer: rectangle, square, parallelogram, regular hexagon.
7-8 Symmetry Course 3 Learn to identify symmetry in figures.
7-8 Symmetry Course 3 Vocabulary line symmetry line of symmetry rotational symmetry
7-8 Symmetry Course 3 Nature provides beautiful examples of symmetry, such as the wings of a butterfly or petals of a flower. Symmetric objects have parts that are congruent. A figure has line symmetry if you can draw a line through it so the the two sides are mirror images of each other. The line is called line of symmetry.
7-8 Symmetry Helpful Hint If you fold a figure on the line of symmetry, the halves match exactly. Course 3
7-8 Symmetry Course 3 Additional Example 1A: Drawing Figures With Line Symmetry Complete the figure. The dashed line is the line of symmetry.
7-8 Symmetry Course 3 Additional Example 1B: Drawing Figures With Line Symmetry Continued Complete the figure. The dashed line is the line of symmetry.
7-8 Symmetry Course 3 Check It Out: Example 1A Complete the figure. The dashed line is the line of symmetry.
7-8 Symmetry Course 3 Check It Out: Example 1B Complete the figure. The dashed line is the line of symmetry.
7-8 Symmetry 6-fold rotational symmetry 8-fold rotational symmetry Course 3 A figure has rotational symmetry if you can rotate the figure around some point so that it coincides with itself. The point is the center of rotation, and the amount of rotation must be less than one full turn or 360°. 6-fold and 8-fold rotational symmetry mean that the figures coincide with themselves 6 times and 8 times respectively, within one full turn.
7-8 Symmetry Course 3 Additional Example 2A: Drawing Figures With Rotational Symmetry Complete the figure. The point is the center of rotation. 2-fold The figure coincides with itself every 180°
7-8 Symmetry Course 3 Additional Example 2B: Drawing Figures With Rotational Symmetry Continued Complete the figure. The point is the center of rotation. 5-fold The figure coincides with itself every 72°
7-8 Symmetry Course 3 Check It Out: Example 2A Complete the figure. The point is the center of rotation. 8-fold The figure coincides with itself every 45°
7-8 Symmetry Course 3 Check It Out: Example 2B Complete the figure. The point is the center of rotation. 10-fold The figure coincides with itself every 36°
7-8 Symmetry Course 3 Lesson Quiz: Part I Does the figure described have symmetry? yes 1. a regular hexagon 2. the letter F no yes 3. the letter M
7-8 Symmetry Course 3 Lesson Quiz: Part II 4. Complete the figure. The dashed line is the line of symmetry.