Isosceles and Equilateral Triangles

Front

What do the angles in an equilateral triangle measure?

Back

60°, 60°, 60°

Front

What is an isosceles triangle?

Back

A triangle with at least two equal sides and two equal angles.

Front

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

Back

180°

Front

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

Back

Isosceles triangle.

Front

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

Back

All sides are equal, and all angles measure 60°.

Front

How do you find the length of a side in an isosceles triangle if you know the base and the height?

Back

Use the Pythagorean theorem.

Front

What is the formula for the area of a triangle?

Back

Area = 1/2 * base * height.

Front

What is the measure of each angle in an equilateral triangle?

Back

60°.

Front

If the length of one side of an equilateral triangle is 6, what is the perimeter?

Back

18 (6 + 6 + 6).

Front

What is the measure of the vertex angle in an isosceles triangle if the base angles are 40°?

Back

100°.