Dilations

Front

What is a dilation in geometry?

Back

A dilation is a transformation that produces a figure similar to the original by enlarging or reducing it, using a center point and a scale factor.

Front

True or False: A dilation produces a congruent figure.

Back

False. A dilation produces a similar figure, not a congruent one.

Front

What is the scale factor in a dilation?

Back

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

Front

If the scale factor is greater than 1, what happens to the figure?

Back

The figure is enlarged.

Front

If the scale factor is less than 1, what happens to the figure?

Back

The figure is reduced.

Front

What are similar figures?

Back

Similar figures have the same shape but different sizes.

Front

How do you find the coordinates of a point after a dilation with a scale factor of k?

Back

Multiply each coordinate of the point by the scale factor k.

Front

What are the coordinates of point B(4,9) after a dilation with a scale factor of 2?

Back

B' (8, 18) because (4*2, 9*2) = (8, 18).

Front

What are the coordinates of point A(3,6) after a dilation with a scale factor of 2?

Back

A' (6, 12) because (3*2, 6*2) = (6, 12).

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.