12/4 Congruent Transformations Warm Up

Front

What is a reflection in geometry?

Back

A reflection is a transformation that flips a figure over a line, creating a mirror image.

Front

What happens to the coordinates of a point when it is reflected over the y-axis?

Back

The x-coordinate changes sign, while the y-coordinate remains the same. For example, (x, y) becomes (-x, y).

Front

What is the rule for reflecting a point (x, y) over the x-axis?

Back

The y-coordinate changes sign, so (x, y) becomes (x, -y).

Front

What is a rotation in geometry?

Back

A rotation is a transformation that turns a figure around a fixed point, called the center of rotation.

Front

What is the rule for a 90° clockwise rotation of a point (x, y)?

Back

The coordinates change to (y, -x).

Front

What is the rule for a 180° rotation about the origin for a point (x, y)?

Back

The coordinates change to (-x, -y).

Front

What is the difference between a reflection and a rotation?

Back

A reflection flips a figure over a line, while a rotation turns a figure around a point.

Front

What does it mean for two figures to be congruent?

Back

Two figures are congruent if they have the same shape and size, but may be in different orientations.

Front

How do you identify the axis of reflection for a triangle?

Back

The axis of reflection is the line over which the triangle is flipped to create its mirror image.

Front

What is the effect of a 90° counterclockwise rotation on the coordinates (x, y)?

Back

The coordinates change to (-y, x).