12/16: (12) Proportions & Similarity

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

What does it mean for two triangles to be similar?

Back

Two triangles are similar if their corresponding angles are equal and their corresponding sides are in proportion.

Front

What is the property of corresponding angles in similar triangles?

Back

The corresponding angles of two similar triangles are congruent.

Front

What is the second property of similar triangles?

Back

Corresponding sides are equally proportional.

Front

Back

Front

How do you find the length of a side in similar triangles?

Back

Use the property of proportions: set up a ratio of corresponding sides and solve for the unknown.

Front

What is the formula for finding the height of an object using shadows?

Back

If two objects cast shadows, the ratio of their heights is equal to the ratio of the lengths of their shadows.

Front

If a telephone booth is 8ft tall and casts a shadow of 4ft, what is the height of a lawn gnome that casts a 2ft shadow?

Back

4 ft.

Front

What is the relationship between the sides of similar triangles?

Back

The ratios of the lengths of corresponding sides are equal.

Front

What is the formula for the area of similar figures?

Back

The ratio of the areas of two similar figures is equal to the square of the ratio of their corresponding sides.