solving proportions/similar figures

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 variable.

Front

What are similar figures?

Back

Similar figures are shapes that have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

If two triangles are similar, what can be said about their corresponding sides?

Back

The lengths of their corresponding sides are proportional.

Front

What is the formula for finding the missing side in similar triangles?

Back

If triangle A and triangle B are similar, then a/b = c/d, where a and c are corresponding sides.

Front

Solve for x: 3/4 = x/16

Back

x = 12.

Front

Solve for x: 5/x = 15/9

Back

x = 3.

Front

If two figures are similar and the scale factor is 2:3, what does this mean?

Back

It means that for every 2 units in the first figure, there are 3 units in the second figure.

Front

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

Back

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

Front

If the sides of two similar rectangles are in the ratio 1:4, what is the ratio of their areas?

Back

The ratio of their areas is 1:16.