Unit 3 Geometry Review (IM)

Front

What is a dilation in geometry?

Back

A dilation is a transformation that alters the size of a figure but maintains its shape. It is defined by a center point and a scale factor.

Front

What is the scale factor in a dilation?

Back

The scale factor is a number that describes how much a figure is enlarged or reduced during a dilation. A scale factor greater than 1 enlarges the figure, while a scale factor between 0 and 1 reduces it.

Front

If angle ABC measures 90 degrees, what will be the measure of angle A'B'C' after a dilation with a scale factor of 1/3?

Back

90 degrees (the measure of angles remains unchanged during dilation).

Front

How do you determine the center of dilation?

Back

The center of dilation is the point from which all points of the figure are expanded or contracted. It can be found by tracing lines from corresponding points of the original and dilated figures.

Front

What is the relationship between corresponding angles in similar figures?

Back

Corresponding angles in similar figures are equal.

Front

What is the formula for solving proportions?

Back

If a/b = c/d, then ad = bc.

Front

If angle BCA = 65 degrees, how do you find angle BAC in triangle ABC?

Back

Use the triangle sum theorem: the sum of the angles in a triangle is 180 degrees. Therefore, angle BAC = 180 - (angle ABC + angle BCA).

Front

What is the triangle sum theorem?

Back

The triangle sum theorem states that the sum of the interior angles of a triangle is always 180 degrees.

Front

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

Back

The scale factor can be found by dividing the length of a side of the image by the length of the corresponding side of the original figure.

Front

What is the definition of similar figures?

Back

Similar figures are figures that have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are proportional.