Illustrative Math Grade 8 Unit 2 Test Review

Front

What is the scale factor in a dilation if the origin is the center and the image is twice the size of the original?

Back

2

Front

In a dilation, what mathematical operation is used with the scale factor?

Back

Multiplication

Front

What type of figures are created by dilations?

Back

Similar figures, but not congruent.

Front

How do you find the slope of a line given two points (x1, y1) and (x2, y2)?

Back

Slope = (y2 - y1) / (x2 - x1)

Front

What is the image of the point B (4,9) under a dilation with center at the origin and a scale factor of 2?

Back

B' (8, 18)

Front

Define dilation in geometry.

Back

A transformation that produces an image that is the same shape as the original, but is a different size.

Front

What is the relationship between the original figure and its dilated image?

Back

The original figure and its dilated image are similar.

Front

If a point (x, y) is dilated by a scale factor of k, what is the new coordinate?

Back

(kx, ky)

Front

What happens to the distances between points in a dilation?

Back

Distances are multiplied by the scale factor.

Front

What is the scale factor if a figure is reduced to half its size?

Back

1/2