#5.4 Equilateral and Isosceles Triangles

Front

What is an equilateral triangle?

Back

A triangle with all three sides of equal length and all three angles equal to 60 degrees.

Front

What is an isosceles triangle?

Back

A triangle with at least two sides of equal length and the angles opposite those sides are equal.

Front

What are the legs of an isosceles triangle?

Back

The two congruent sides of an isosceles triangle.

Front

What is the base of an isosceles triangle?

Back

The side of an isosceles triangle that is not congruent to the other two sides.

Front

How do you find the height of an isosceles triangle?

Back

Draw a perpendicular line from the vertex opposite the base to the midpoint of the base.

Front

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

Back

180 degrees.

Front

If two angles of a triangle are equal, what type of triangle is it?

Back

It is an isosceles triangle.

Front

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

Back

All angles are equal (60 degrees) and all sides are equal.

Front

How do you determine if a triangle is scalene?

Back

A triangle is scalene if all three sides are of different lengths.

Front

What is the Pythagorean theorem?

Back

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.