Dilations and scale factors

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.

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

What scale factor produces an enlargement?

Back

A scale factor greater than 1 produces an enlargement.

Tags

CCSS.8.G.A.3

Front

What scale factor produces a reduction?

Back

A scale factor less than 1 produces a reduction.

Tags

CCSS.8.G.A.3

Front

If a triangle is dilated by a scale factor of 2, what happens to its size?

Back

The triangle's size doubles.

Tags

CCSS.8.G.A.3

Front

If the coordinates of point A are (2, 3) and it is dilated by a scale factor of 3, what are the new coordinates A'?

Back

A' = (6, 9) because each coordinate is multiplied by 3.

Tags

CCSS.8.G.A.3

Front

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

Back

A scale factor of 1 means the figure remains the same size.

Tags

CCSS.8.G.A.3

Front

If ΔABC is dilated to ΔDEF with a scale factor of 2, what is the relationship between their areas?

Back

The area of ΔDEF is 4 times the area of ΔABC because area scales by the square of the scale factor.

Tags

CCSS.7.G.A.1

Front

How do you find the scale factor between two similar figures?

Back

Divide the length of a side of the image by the length of the corresponding side of the original figure.

Tags

CCSS.7.G.A.1

Front

If a figure is dilated by a scale factor of 1/2, what type of transformation is this?

Back

This is a reduction.

Tags

CCSS.8.G.A.3