7.5AC STAAR Review Similarity

Front

What does it mean for two triangles to be similar?

Back

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

Front

What is a proportion in mathematics?

Back

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

Front

How can you find the length of a side in a similar triangle?

Back

You can use the proportion of the lengths of corresponding sides to find the unknown length.

Front

If triangle HJK is similar to triangle LMN, how do you set up a proportion to find LM?

Back

Set up the proportion using the lengths of corresponding sides, such as HJ/LM = HK/LN.

Front

What is the scale factor in similar figures?

Back

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

Front

How do you calculate the scale factor between two similar triangles?

Back

Divide the length of a side of one triangle by the length of the corresponding side of the other triangle.

Front

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

Back

The ratio of their areas is equal to the square of the ratio of their corresponding side lengths.

Front

If a building is 125 meters tall and is drawn at a height of 25 cm, what is the scale factor?

Back

The scale factor is 1:5, since 125 meters to 25 cm is a ratio of 5:1.

Front

How do you convert feet to inches when using a scale?

Back

Multiply the number of feet by 12 to convert to inches.

Front

What is the height of a model of the Washington Monument if 1 inch represents 15 feet?

Back

The model height is 37 inches, calculated by dividing 555 feet by 15.