Equilateral and Isosceles Triangles

Front

What is an equilateral triangle?

Back

An equilateral triangle is a triangle in which all three sides are of equal length and all three angles are equal, each measuring 60 degrees.

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 a triangle?

Back

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

Front

How do you identify 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

What are congruent sides in a triangle?

Back

Congruent sides are sides that are of equal length.

Front

What is the sum of the interior angles of a triangle?

Back

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

Front

How do you find the measure of an unknown angle in an isosceles triangle?

Back

To find the measure of an unknown angle in an isosceles triangle, use the fact that the two base angles are equal and the sum of all angles is 180 degrees.

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 also equal.

Front

What is the formula for the area of a triangle?

Back

The area of a triangle can be calculated using the formula: Area = 1/2 * base * height.

Front

How do you determine if a triangle is equilateral?

Back

A triangle is equilateral if all three sides are equal in length.