Isosceles and Equilateral Triangles

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 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 the sum of the interior angles of a triangle?

Back

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

Front

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

Back

The sides opposite the equal angles are also equal in length.

Front

How do you find the height of an isosceles triangle?

Back

To find the height of an isosceles triangle, draw a perpendicular line from the vertex opposite the base to the midpoint of the base.

Front

What is the relationship between the base angles of an isosceles triangle?

Back

The base angles of an isosceles triangle are equal.

Front

If the length of the base of an isosceles triangle is 10 and the equal sides are 12, what is the height?

Back

The height can be found using the Pythagorean theorem: height = √(12² - (10/2)²) = √(144 - 25) = √119 ≈ 10.91.

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

In an equilateral triangle, what is the measure of each angle?

Back

In an equilateral triangle, each angle measures 60 degrees.

Front

What is the relationship between the sides of an equilateral triangle?

Back

All sides of an equilateral triangle are equal in length.