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 equal.

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 a triangle?

Back

To find the measure of an unknown angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

What is the vertex angle in an isosceles triangle?

Back

The vertex angle in an isosceles triangle is the angle opposite the base, which is formed by the two equal sides.

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 two angles of a triangle are equal, what can be said about the sides opposite those angles?

Back

If two angles of a triangle are equal, the sides opposite those angles are also equal in length.

Front

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

Back

In an equilateral triangle, all sides are equal, and all angles are equal, each measuring 60 degrees.

Front

How do you determine if a triangle is isosceles?

Back

A triangle is isosceles if at least two of its sides are of equal length.

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.