Dilations and Scale Factor

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but keeps its shape, using 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 the scale factor is greater than 1, what type of dilation is it?

Back

It is an enlargement.

Tags

CCSS.8.G.A.3

Front

If the scale factor is less than 1, what type of dilation is it?

Back

It is a reduction.

Tags

CCSS.8.G.A.3

Front

What happens to the coordinates of a point (x, y) when it is dilated by a scale factor of k?

Back

The new coordinates become (kx, ky).

Tags

CCSS.8.G.A.3

Front

How do you determine if a dilation is an enlargement or reduction?

Back

Compare the scale factor to 1: if >1, it's an enlargement; if <1, it's a reduction.

Tags

CCSS.8.G.A.3

Front

What is the scale factor if the original length is 3 and the new length is 1?

Back

The scale factor is 1/3.

Tags

CCSS.7.G.A.1

Front

What is the scale factor if the original length is 2 and the new length is 8?

Back

The scale factor is 4.

Tags

CCSS.7.G.A.1

Front

What is the effect of a scale factor of 1 on a figure?

Back

The figure remains unchanged.

Tags

CCSS.8.G.A.3

Front

If triangle ABC is dilated to triangle A'B'C' with a scale factor of 2, what happens to the area?

Back

The area increases by a factor of 2^2 = 4.

Tags

CCSS.7.G.A.1