Dilation & Scale Factor

Front

What is dilation in geometry?

Back

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

Tags

CCSS.8.G.A.3

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.

Tags

CCSS.8.G.A.3

Front

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

Back

The figure becomes larger.

Tags

CCSS.8.G.A.3

Front

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

Back

The figure becomes smaller.

Tags

CCSS.8.G.A.3

Front

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

Back

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

Tags

CCSS.8.G.A.3

Front

What are the coordinates of point A(3, 4) after a dilation with a scale factor of 2?

Back

A' (6, 8) because 3*2 = 6 and 4*2 = 8.

Tags

CCSS.8.G.A.3

Front

What are the coordinates of point B(5, 10) after a dilation with a scale factor of 1/2?

Back

B' (2.5, 5) because 5*1/2 = 2.5 and 10*1/2 = 5.

Tags

CCSS.8.G.A.3

Front

What is the effect of a negative scale factor on a figure?

Back

A negative scale factor reflects the figure across the center point and scales it.

Tags

CCSS.8.G.A.3

Front

If point (8, 12) is dilated to (2, 3), what is the scale factor?

Back

The scale factor is 1/4.

Tags

CCSS.8.G.A.3

Front

What is the image of point C(6, 9) under a dilation with a scale factor of 3?

Back

C' (18, 27) because 6*3 = 18 and 9*3 = 27.

Tags

CCSS.8.G.A.3