Topic 7: Dilations and Similarity II

Front

What is a dilation in geometry?

Back

A dilation is a transformation that changes the size of a figure but not its shape, using a scale factor.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, the dimensions of a figure in a dilation.

Front

If a scale factor is greater than 1, what happens to the figure?

Back

The figure enlarges.

Front

If a scale factor is less than 1, what happens to the figure?

Back

The figure shrinks.

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but different sizes.

Front

What is the relationship between corresponding angles in similar figures?

Back

Corresponding angles in similar figures are equal.

Front

What is the relationship between corresponding sides in similar figures?

Back

The ratios of the lengths of corresponding sides in similar figures are equal.

Front

How do you find the height of a tree using similar triangles?

Back

You can use the ratio of the heights of the tree and a smaller object to the lengths of their shadows.

Front

What is the formula for finding the area of a similar figure?

Back

The area of a similar figure is proportional to the square of the scale factor.

Front

What is the formula for finding the perimeter of a similar figure?

Back

The perimeter of a similar figure is proportional to the scale factor.