Five-Minute Check (over Lesson 6-4)

Main Idea and Vocabulary

Targeted TEKS

Example 1: Identify Line Symmetry

Example 2: Identify Line Symmetry

Example 3: Identify Rotational Symmetry

Example 4: Use a Rotation

• line symmetry

• line of symmetry• rotational symmetry• angle of rotation

• Identify line symmetry and rotational symmetry.

Identify Line Symmetry

Determine whether the figure has line symmetry. If it does, draw all lines of symmetry. If not, write none.

Answer: This figure has one vertical line of symmetry.

BOTANY Determine whether the leaf has line symmetry. If it does, draw all lines of symmetry. If not, write none.

Answer: This figure has one vertical line of symmetry.

Identify Line Symmetry

Determine whether the figure has line symmetry. If it does, trace the figure and draw all lines of symmetry. If not, write none.

Answer: This figure has no lines of symmetry.

Determine whether the figure has line symmetry. If it does, trace the figure and draw all lines of symmetry. If not, write none.

Answer: This figure has one vertical line of symmetry.

Identify Rotational Symmetry

FLOWERS Determine whether the flower design has rotational symmetry. Write yes or no. If yes, name its angle(s) of rotation.

Identify Rotational Symmetry

Answer: Yes, this figure has rotational symmetry. It will match itself after being rotated 90, 180, and 270.

1. A

2. B

3. C

4. D

0%0%0%0%

A¤B¤C¤D B C DA. yes, 90° B. yes, 120°

C. yes, 180° D. no

FLOWERS Determine whether the flower design has rotational symmetry. Write yes or no. If yes, name its angle(s) of rotation.

ARCHITECTURE A rosette is a painted or sculptured ornament, usually circular, having designs that radiate symmetrically from the center. Copy and complete the picture of the rosette shown so that the completed figure has rotational symmetry with 90, 180, and 270 as its angles of rotation.

Use a Rotation

Use the procedure described above and the points indicated to rotate the figure 90, 180, and 270 counterclockwise. Use a 90 rotation clockwise to produce the same rotation as a 270 rotation counterclockwise.

Answer:

Use a Rotation

90° counterclockwise 180° counterclockwise 90° clockwise

DESIGN Copy and complete the figure so that the completed design has rotational symmetry with 90, 180, and 270 as its angles of rotation.

Answer:

http://www.tx.msmath3.com/

Five-Minute Check (over Lesson 6-5)

Main Idea and Vocabulary

Targeted TEKS

Example 1: Draw a Reflection

Example 2: Reflect a Figure Over an Axis

Example 3: Reflect a Figure Over an Axis

Example 4: Use a Reflection

• reflection

• line of reflection• transformation

• Graph reflections on a coordinate plane.

Draw a Reflection

Copy trapezoid STUV below on graph paper. Then draw the image of the figure after a reflection over the given line.

Draw a Reflection

Step 1 Count the number of units between each vertex and the line of reflection.

Step 2 Plot a point for each vertex the same distance away from the line on the other side.

Step 3 Connect the new vertices to form the image of trapezoid STUV, trapezoid S'T'U'V'.

Answer:

Copy trapezoid TRAP below on graph paper. Then draw the image of the figure after a reflection over the given line.

Answer:

Reflect a Figure Over an Axis

Graph quadrilateral EFGH with vertices E(–4, 4), F(3, 3), G(4, 2) and H(–2, 1). Then graph the image of EFGH after a reflection over the x-axis and write the coordinates of its vertices.

Reflect a Figure Over an Axis

The coordinates of the vertices of the image are E'(–4, –4), F'(3, –3), G'(4, –2), and H'(–2, –1).

Notice that the y-coordinate of a point reflected over the x-axis is the opposite of the y-coordinate of the original point. same

H(–2, 1)

opposites

E(–4, 4)

F(3, 3)

G(4, 2)

H'(–2, –1)

G'(4, –2)

F'(3, –3)

E'(–4, –4)

Reflect a Figure Over an Axis

Answer: E'(–4, –4), F'(3, –3), G'(4, –2), and H'(–2, –1).

Graph quadrilateral QUAD with vertices Q(2, 4), U(4, 1), A(–1, 1), and D(–3, 3). Then graph the image of QUAD after a reflection over the x-axis, and write the coordinates of its vertices.

Answer: Q'(2, –4), U'(4, –1), A'(–1, –1), and D'(–3, –3).

Reflect a Figure Over an Axis

Graph quadrilateral ABCD with vertices A(1, 3), B(4, 0), C(3, –4), and D(1, –2). Then graph the image of ABCD after a reflection over the y-axis, and write the coordinates of its vertices.

Reflect a Figure Over an Axis

The coordinates of the vertices of the image are A'(–1, 3), B'(–4, 0), C'(–3, –4), and D'(–1, –2).

Notice that the x-coordinate of a point reflected over the y-axis is the opposite of the x-coordinate of the original point. opposites

D(1, –2)

same

A(1, 3)

B(4, 0)

C(3, –4)

D'(–1, –2)

C'(–3, –4)

B'(–4, 0)

A'(–1, 3)

Reflect a Figure Over an Axis

Answer: A'(–1, 3), B'(–4, 0), C'(–3, –4), and D'(–1, –2).

Graph quadrilateral ABCD with vertices A(2, 2), B(5, 0), C(4, –2), and D(2, –1). Then graph the image of ABCD after a reflection over the y-axis, and write the coordinates of its vertices.

Answer: A'(–2, 2), B'(–5, 0), C'(–4, –2), and D'(–2, –1).

ARCHITECTURE Copy and complete the office floor plan shown below so that the completed office has a horizontal line of symmetry.

You can reflect the half of the office floor plan shown over the indicated horizontal line.Find the distance from each vertex on the figure to the line of reflection.Then plot a point the same distance away on the opposite side of the line. Connect vertices as appropriate.

Answer:

Use a Reflection

GAMES Copy and complete the game board shown below so that the completed game board has a vertical line of symmetry.

Answer:

Interactive Lab: Reflections