Day 63 - Proportions, Scale Factor & Similarity

Front

What is a proportion?

Back

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

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then solve for the unknown variable.

Front

What is a scale factor?

Back

A scale factor is a number that scales, or multiplies, some quantity. It is used to determine the size of similar figures.

Front

If the scale factor from ΔDEF to ΔABC is 1/2, what does this mean?

Back

It means that every side of ΔDEF is half the length of the corresponding side in ΔABC.

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, and their corresponding angles are equal.

Front

How do you find a missing side in similar figures?

Back

To find a missing side, set up a proportion using the lengths of the corresponding sides of the similar figures.

Front

What is the relationship between the sides of similar triangles?

Back

The ratios of the lengths of corresponding sides of similar triangles are equal.

Front

If AB / BM = ? / CD, what is the missing term if AC is known?

Back

The missing term is AC.

Front

What is the formula for finding the scale factor between two similar figures?

Back

Scale Factor = Length of a side of the new figure / Length of the corresponding side of the original figure.

Front

How do you determine if two ratios form a proportion?

Back

Two ratios form a proportion if their cross products are equal.