Introduction to Chapter 9 Vocabulary

Front

Transformations

Back

An operation that maps an original figure called the pre-image onto a new figure called the image.

Can change the size, position, or shape of a figure.

Front

Reflections

Back

A FLIP over a line called the line of reflection.

Each point and its image are the same distance from the line of reflection.

Front

Translations

Back

To vertically and/or horizontally SLIDE a figure.

Front

Rotations

Back

A TURN around a fixed point called the center of dilation.

The figure rotates at a specific angle and direction.

Front

Line Symmetry

Back

A figure has line symmetry if the figure can be mapped onto itself by a reflection in a line.

Front

Point Symmetry

Back

A figure has point symmetry if the figure is mapped onto itself by rotating the figure 180 degrees about a center point.

Front

Rotational Symmetry

Back

A figure has rotational symmetry if the figure is mapped onto itself by rotating the figure less than 360 degrees about a center point.

Front

Dilations

Back

The enlargement or reduction of a figure.

The scale factor indicates how much the figure will enlarge or reduce.

Front

Scale Factor

Back

The number the figures is doing to be multiplied by.

Variable: k

k>1: enlargement

k<1: reduction