Similar Triangles

Front

What are similar triangles?

Back

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

Front

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

Back

The corresponding sides are proportional.

Front

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

Back

The corresponding angles are congruent.

Front

What is the AA criterion for triangle similarity?

Back

If two angles of one triangle are equal to two angles of another triangle, the triangles are similar.

Front

What is the SSS criterion for triangle similarity?

Back

If the sides of one triangle are proportional to the sides of another triangle, the triangles are similar.

Front

What is the SAS criterion for triangle similarity?

Back

If two sides of one triangle are proportional to two sides of another triangle and the included angle is equal, the triangles are similar.

Front

If triangle ABC is similar to triangle DEF, and AB = 4, AC = 6, and DE = 8, what is the length of DF?

Back

DF = 12 (using the proportionality of sides).

Front

If two triangles have a ratio of their corresponding sides of 2:3, what is the ratio of their areas?

Back

The ratio of their areas is 4:9 (the square of the ratio of the sides).

Front

What does it mean if two figures are not similar?

Back

It means that their corresponding angles are not equal and/or their corresponding sides are not proportional.

Front

How can you determine if two triangles are similar using the angle-angle (AA) criterion?

Back

If you can show that two angles of one triangle are equal to two angles of another triangle, then the triangles are similar.