Introduction to 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 in proportion.

Front

What is the property of corresponding angles in similar triangles?

Back

All corresponding angles in similar triangles are congruent.

Front

What is the property of corresponding sides in similar triangles?

Back

The lengths of corresponding sides are proportional.

Front

If triangle ABC is similar to triangle DEF, and the length of side AB is 6 cm and side DE is 9 cm, what is the ratio of their corresponding sides?

Back

The ratio is 6:9 or 2:3.

Front

What is the definition of corresponding sides?

Back

Sides in two or more similar figures that are in the same relative position.

Front

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

Back

The ratio of their areas is the square of the ratio of their corresponding sides.

Front

What is the relationship between the angles of similar triangles?

Back

The angles of similar triangles are equal.

Front

If triangle PQR is similar to triangle XYZ and the length of side PQ is 8 in. and side XY is 12 in., what is the length of side XZ if side PR is 10 in.?

Back

XZ = (10 in. / 8 in.) * 12 in. = 15 in.

Front

What does it mean if two triangles are not similar?

Back

It means that their corresponding angles are not equal or their corresponding sides are not in proportion.

Front

What is the significance of the AA criterion for similarity?

Back

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