Rotations of figures

Front

What is the definition of 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 certain angle in a specified direction.

Front

What are the coordinates of a point after a 90-degree rotation counterclockwise around the origin?

Back

If a point has coordinates (x, y), after a 90-degree rotation counterclockwise around the origin, the new coordinates will be (-y, x).

Front

What is the center of dilation?

Back

The center of dilation is a fixed point in the plane about which all points are expanded or contracted during a dilation.

Front

What happens to the size of a figure during a dilation?

Back

During a dilation, the size of the figure changes; it can either be enlarged or reduced, but the shape remains the same.

Front

What is the scale factor in a dilation?

Back

The scale factor is a number that describes how much a figure is enlarged or reduced during a dilation.

Front

How do you determine the coordinates of a dilated figure?

Back

To determine the coordinates of a dilated figure, multiply each coordinate of the original figure by the scale factor.

Front

What is an image in the context of transformations?

Back

An image is the result of a transformation applied to a figure.

Front

What is the difference between enlargement and reduction in dilations?

Back

Enlargement increases the size of a figure (scale factor greater than 1), while reduction decreases the size of a figure (scale factor less than 1).

Front

What is the effect of a dilation with a scale factor of 1?

Back

A dilation with a scale factor of 1 results in no change to the size or shape of the figure; the image is congruent to the original.

Front

What does it mean for dilations to preserve shape?

Back

Dilations preserve the shape of a figure, meaning that the angles and relative proportions of the sides remain unchanged.