Isosceles Triangles

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length. The angles opposite these sides are also equal.

Front

What is the base of an isosceles triangle?

Back

The base of an isosceles triangle is the side that is not equal in length to the other two sides.

Front

If the base angles of an isosceles triangle are equal, what can be said about the vertex angle?

Back

The vertex angle is equal to 180° minus twice the measure of one of the base angles.

Front

How do you find the vertex angle if the base angle is known?

Back

If the base angle is known, the vertex angle can be calculated using the formula: Vertex Angle = 180° - 2(Base Angle).

Front

What is the sum of the angles in any triangle?

Back

The sum of the angles in any triangle is always 180°.

Front

In a right isosceles triangle, what are the measures of the angles?

Back

In a right isosceles triangle, one angle measures 90°, and the other two angles each measure 45°.

Front

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

Back

In an isosceles triangle, the angles opposite the equal sides are equal, and the side opposite the vertex angle is the base.

Front

If the lengths of the two equal sides of an isosceles triangle are 10 cm, what is the minimum length of the base?

Back

The minimum length of the base must be greater than 0 cm and less than 20 cm (the sum of the lengths of the two equal sides).

Front

What is the formula for the area of an isosceles triangle?

Back

The area of an isosceles triangle can be calculated using the formula: Area = (Base * Height) / 2.

Front

How do you determine if a triangle is isosceles based on its side lengths?

Back

A triangle is isosceles if at least two of its side lengths are equal.