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.

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 does 'acute triangle' mean?

Back

An acute triangle is a triangle where all three angles are less than 90 degrees.

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

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

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

Back

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

Front

How do you find the height of an isosceles triangle?

Back

The height can be found by drawing a perpendicular line from the vertex opposite the base to the midpoint of the base.

Front

What is the Pythagorean theorem?

Back

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides (a² + b² = c²).

Front

If a triangle has angles measuring 30 degrees and 60 degrees, what is the measure of the third angle?

Back

The third angle measures 90 degrees.

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.