3.5 Isosceles Triangles Closer

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length and the angles opposite those sides are also equal.

Front

What is the vertex angle in an isosceles triangle?

Back

The vertex angle is the angle formed by the two equal sides of an isosceles triangle.

Front

If the base angles of an isosceles triangle are each 40°, what is the measure of the vertex angle?

Back

100°

Front

In an isosceles triangle, if one base angle is 32°, what is the measure of the other base angle?

Back

32° (base angles are equal in an isosceles triangle).

Front

How do you find the vertex angle if the base angles are known?

Back

Subtract the sum of the base angles from 180° (Vertex angle = 180° - 2 * base angle).

Front

What is the base of an isosceles triangle?

Back

The base is the side that is not equal in length to the other two sides.

Front

In triangle ABC, if AB = AC, which angle is the vertex angle?

Back

Angle A is the vertex angle.

Front

If the base of an isosceles triangle measures 10 cm and the equal sides measure 13 cm, what is the height of the triangle?

Back

Using the Pythagorean theorem, the height is approximately 12 cm.

Front

What is the relationship between the angles in an isosceles triangle?

Back

The angles opposite the equal sides are equal.

Front

If an isosceles triangle has a vertex angle of 120°, what are the measures of the base angles?

Back

Each base angle measures 30°.