Isosceles + Triangles Congruence

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length.

Front

What is the property of angles in an isosceles triangle?

Back

The angles opposite the equal sides of an isosceles triangle are also equal.

Front

How do you find the missing angle in a triangle?

Back

To find the missing angle in a triangle, use the fact that the sum of all angles in a triangle is 180°.

Front

If two angles of a triangle are 40° and 60°, what is the measure of the third angle?

Back

The third angle is 80° (180° - 40° - 60°).

Front

What is the congruence criterion for isosceles triangles?

Back

If two sides of a triangle are equal, then the angles opposite those sides are equal.

Front

What does the term 'congruent triangles' mean?

Back

Congruent triangles are triangles that are identical in shape and size, meaning all corresponding sides and angles are equal.

Front

What is the Angle-Side-Angle (ASA) congruence criterion?

Back

The ASA criterion states that if two angles and the included side of one triangle are equal to two angles and the included side of another triangle, the triangles are congruent.

Front

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

Back

The SAS criterion states that if two sides and the included angle of one triangle are equal to two sides and the included angle of another triangle, the triangles are congruent.

Front

What is the Side-Side-Side (SSS) congruence criterion?

Back

The SSS criterion states that if all three sides of one triangle are equal to all three sides of another triangle, the triangles are congruent.

Front

If triangle ABC is isosceles with AB = AC, what can be said about angles B and C?

Back

Angles B and C are equal.