Dilations and other Transformations

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but not its shape, using a scale factor.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, the dimensions of a figure during a dilation.

Front

How do you determine the scale factor when given original and dilated points?

Back

To find the scale factor, divide the coordinates of the dilated point by the corresponding coordinates of the original point.

Front

What is the algebraic rule for a 90° counterclockwise rotation?

Back

(x, y) transforms to (-y, x).

Front

What happens to a triangle when it is dilated by a scale factor greater than 1?

Back

The triangle is enlarged.

Front

What happens to a triangle when it is dilated by a scale factor less than 1?

Back

The triangle is reduced.

Front

If triangle ABC is dilated by a scale factor of 3/4, what is the relationship between triangle ABC and triangle A'B'C'?

Back

Triangle A'B'C' is a reduction of triangle ABC.

Front

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

Back

Multiply the original coordinates by the scale factor.

Front

What is the center of dilation?

Back

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

Front

If point (4, 6) is dilated by a scale factor of 2, what are the new coordinates?

Back

(8, 12).