Dilations

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 does it mean if the scale factor is greater than 1?

Back

If the scale factor is greater than 1, the figure is enlarged.

Tags

CCSS.8.G.A.3

Front

What does it mean if the scale factor is less than 1?

Back

If the scale factor is less than 1, the figure is reduced.

Tags

CCSS.8.G.A.3

Front

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

Back

Compare the scale factor to 1: if it's greater than 1, it's an enlargement; if it's less than 1, it's a reduction.

Tags

CCSS.8.G.A.3

Front

If a rectangle is dilated with a scale factor of 2, what happens to its dimensions?

Back

Each dimension of the rectangle is multiplied by 2, making it twice as large.

Tags

CCSS.8.G.A.3

Front

What is the dilation rule for a scale factor of 1/2?

Back

The dilation rule is (1/2 x, 1/2 y), which reduces the size of the figure by half.

Tags

CCSS.8.G.A.3

Front

If the coordinates of a point are (x, y), what are the new coordinates after a dilation with a scale factor of k?

Back

The new coordinates will be (kx, ky).

Tags

CCSS.8.G.A.3

Front

What is the effect of a dilation on angles?

Back

Dilation does not change the measures of angles; they remain the same.

Tags

CCSS.8.G.A.3

Front

If Triangle ABC is dilated to Triangle A'B'C' with a scale factor of 3, what happens to the area?

Back

The area of Triangle A'B'C' will be 9 times the area of Triangle ABC, since area scales by the square of the scale factor.

Tags

CCSS.7.G.A.1