4-2 Equilateral and Isosceles Triangle

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 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 congruent, what can be said about the sides opposite those angles?

Back

The sides opposite the congruent angles are also congruent.

Front

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

Back

In an equilateral triangle, all three angles are equal, each measuring 60 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 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

What is the Pythagorean theorem?

Back

Front

If the lengths of two sides of an isosceles triangle are 5 cm each, what is the minimum possible length of the third side?

Back

The minimum possible length of the third side must be greater than the difference of the two equal sides, which is 0 cm. Therefore, the third side must be greater than 0 cm.

Front

What is the definition of congruent angles?

Back

Congruent angles are angles that have the same measure.