12/13 Triangle Similarity Finding the unknown

Front

What is the Triangle Similarity Theorem?

Back

The Triangle Similarity Theorem states that if two triangles have corresponding angles that are equal, then the triangles are similar.

Front

What does it mean for triangles to be similar?

Back

Triangles are similar if their corresponding angles are equal and their corresponding sides are in proportion.

Front

How do you find the unknown side length in similar triangles?

Back

To find the unknown side length, set up a proportion using the lengths of the corresponding sides of the similar triangles.

Front

If triangle ABC is similar to triangle DEF, and AB = 10, DE = 5, what is the ratio of their sides?

Back

The ratio of their sides is 2:1.

Front

What is the sum of the angles in a triangle?

Back

The sum of the angles in a triangle is always 180 degrees.

Front

If two angles of one triangle are equal to two angles of another triangle, what can be concluded?

Back

The two triangles are similar.

Front

What is the Side-Angle-Side (SAS) similarity criterion?

Back

The SAS similarity criterion states that if an angle of one triangle is equal to an angle of another triangle and the sides including these angles are in proportion, then the triangles are similar.

Front

How can you determine if two triangles are not similar?

Back

If the corresponding angles are not equal or the sides are not in proportion, the triangles are not similar.

Front

What is the relationship between the sides of similar triangles?

Back

The lengths of corresponding sides of similar triangles are proportional.

Front

If triangle XYZ is similar to triangle PQR, and XY = 12, PQ = 8, what is the scale factor?

Back

The scale factor is 12:8 or 3:2.