Similarity ACC

Front

What does it mean for two figures to be similar?

Back

Two figures are similar if they have the same shape but not necessarily the same size. Their corresponding angles are equal, and their corresponding sides are proportional.

Front

What is the definition of scale factor in similar figures?

Back

The scale factor is the ratio of the lengths of corresponding sides of two similar figures.

Front

If the scale factor of two similar triangles is 3/4, what is the ratio of their areas?

Back

The ratio of their areas is (3/4)² = 9/16.

Front

What is the relationship between the perimeters of two similar figures?

Back

The ratio of the perimeters of two similar figures is equal to the scale factor.

Front

If triangle ABC is similar to triangle DEF and the length of side AB is 10 cm, what is the length of side DE if the scale factor is 2/5?

Back

The length of side DE is (2/5) * 10 cm = 4 cm.

Front

True or False: All corresponding angles in similar figures are equal.

Back

True.

Front

True or False: Similar figures must have the same area.

Back

False.

Front

If two similar rectangles have a scale factor of 1:3, what is the ratio of their lengths?

Back

The ratio of their lengths is 1:3.

Front

How do you find a missing side length in similar figures?

Back

Set up a proportion using the lengths of corresponding sides and solve for the missing length.

Front

If the perimeter of triangle PQR is 42 cm and triangle XYZ is similar to it with a scale factor of 3/2, what is the perimeter of triangle XYZ?

Back

The perimeter of triangle XYZ is (3/2) * 42 cm = 63 cm.