Math 8: 2.1-4 Review, Dilations

Front

What is a dilation in geometry?

Back

A dilation is a transformation that changes the size of a figure but not its shape, using a center point and a scale factor.

Front

What does the scale factor in a dilation represent?

Back

The scale factor indicates how much the figure is enlarged or reduced. A scale factor greater than 1 enlarges the figure, while a scale factor less than 1 reduces it.

Front

If the scale factor is 2, how does the size of the figure change?

Back

The figure is enlarged to twice its original size.

Front

If the scale factor is 1/2, how does the size of the figure change?

Back

The figure is reduced to half its original size.

Front

What happens to the angles of a polygon during a dilation?

Back

Dilations do not change the angles of a polygon; they remain the same.

Front

How do you determine the new coordinates of a point after dilation?

Back

To find the new coordinates, multiply the distance from the center of dilation to the point 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 A is dilated from center P with a scale factor of 3, what is the relationship between the distance from P to A and the distance from P to the image of A?

Back

The distance from P to the image of A will be three times the distance from P to A.

Front

True or False: A dilation with a scale factor of 0 results in a point.

Back

True.

Front

What is the effect of a negative scale factor in a dilation?

Back

A negative scale factor reflects the figure across the center of dilation and changes its size.