Similarity & Proportions

Front

What is the definition of similar triangles?

Back

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

Front

What is the scale factor in similar figures?

Back

The ratio of the lengths of corresponding sides of two similar figures.

Front

If two triangles are similar, how do you find the length of a missing side?

Back

Use the proportion of the lengths of corresponding sides to set up a ratio and solve for the missing length.

Front

What is the relationship between the angles of similar polygons?

Back

All corresponding angles of similar polygons are equal.

Front

How do you determine if two polygons are similar?

Back

Two polygons are similar if their corresponding angles are equal and the lengths of their corresponding sides are proportional.

Front

If triangle ABC is similar to triangle DEF, and the length of side AB is 4 cm and side DE is 8 cm, what is the scale factor from triangle ABC to triangle DEF?

Back

The scale factor is 1:2.

Front

Solve for x: If triangle ABC is similar to triangle DEF, and the lengths of sides are in the ratio 3:5, and side AB = 9 cm, what is the length of side DE?

Back

15 cm.

Front

What is the formula for finding the area ratio of two similar figures?

Back

The area ratio is the square of the scale factor of the corresponding sides.

Front

If the scale factor of two similar triangles is 2:3, what is the ratio of their areas?

Back

The area ratio is 4:9.

Front

Find the missing length: Triangle ABC is similar to triangle DEF. If AB = 6 cm and DE = 9 cm, and BC = 4 cm, what is the length of EF?

Back

6 cm.