Equilateral triangles have 3 equal sides and 3 equal angles that are always 60 degrees. All of the angles in an equilateral triangle are acute. In addition to this, all equilateral triangles are isoceles triangles because all three sides in an equilateral triangle have to be the same. This means that at least 2 of the sides will be the same. I don't know exactly what goes in your blank, but maybe this information will help you.
