Math 8: 2.1-4 Review, Dilations

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but not its shape. It can be an enlargement or a reduction.

Front

What does the scale factor in a dilation represent?

Back

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

Front

If a point is dilated with a scale factor of 1/2, what happens to its distance from the center of dilation?

Back

The distance from the center of dilation is halved.

Front

What are similar polygons?

Back

Polygons that have the same shape but may differ in size. Their corresponding angles are congruent, and their corresponding sides are in proportion.

Front

What must be true about the corresponding angles of similar polygons?

Back

The corresponding angles must be congruent.

Front

How do you find the image of a point after dilation?

Back

Multiply the coordinates of the point by the scale factor.

Front

What is the image of point B (4,9) under a dilation with a scale factor of 2?

Back

B' (8, 18) is the image of point B after dilation.

Front

What is the result of dilating a point with a scale factor greater than 1?

Back

The point moves away from the center of dilation, resulting in an enlargement.

Front

What is the result of dilating a point with a scale factor less than 1?

Back

The point moves closer to the center of dilation, resulting in a reduction.

Front

If the center of dilation is at the origin, how do you dilate the point (x, y)?

Back

The new coordinates will be (kx, ky), where k is the scale factor.