Rotations and Symmetry

Front

What is a rotation in geometry?

Back

A rotation is a transformation that turns a figure around a fixed point, known as the center of rotation, by a specified angle in a specified direction.

Front

What is the angle of rotation for a 90° clockwise rotation?

Back

A 90° clockwise rotation turns a figure 90 degrees to the right around the center of rotation.

Front

How do you find the coordinates of a point after a 180° rotation about the origin?

Back

To find the new coordinates after a 180° rotation, change the sign of both the x and y coordinates. For example, (-x, -y).

Front

What is line symmetry?

Back

Line symmetry occurs when a figure can be divided into two identical halves that are mirror images of each other along a line.

Front

What is rotational symmetry?

Back

Rotational symmetry is when a figure can be rotated around a center point and still look the same at certain angles of rotation.

Front

How many lines of symmetry does a circle have?

Back

A circle has an infinite number of lines of symmetry.

Front

What is the relationship between the angles of rotation and the number of lines of symmetry?

Back

The number of lines of symmetry in a shape often corresponds to the angles of rotation that map the shape onto itself.

Front

What are the coordinates of a point A(-2, 3) after a 90° clockwise rotation?

Back

A'(3, 2).

Front

What is the result of rotating the point (3, 4) 180° about the origin?

Back

The new coordinates will be (-3, -4).

Front

How do you determine the number of lines of symmetry in a polygon?

Back

Count the number of ways you can draw a line through the shape such that each side is a mirror image of the other.