Classify Triangles by Angle
Triangles can be classified by the size of the angles:
Acute: all angles are less than 90°
Right: one angle has a measure of exactly 90°
Obtuse: one angle has a measure greater than 90°
Triangle can be classified by the lengths of the sides of triangle:
Scalene: no sides are equal to each other
Isosceles: any two sides are equal to each other
Equilateral: all three sides are equal.
Also, Triangle can be classified by the measures of the angles of triangle:
Scalene: no angles are equal to each other
Isosceles: any two angles are equal to each other
Equilateral: all three angles are equal (measure 60°)