how many sides does a triangle have?
Classification of Triangles According to angles If one angle of a triangle is a right angle (90Â°), then it is called a Right triangle. Note that the other two angles are acuâ¦te. If all the angles of a triangle are acute (less than 90Â°), then it is called an acute angled triangle. If one angle of a triangle is obtuse (greater than 90Â°), then it is called an obtuse triangle. Note that the other two angles are acute. According to sides:If any two sides of a triangle are equal, then it is called an Isosceles Triangle. In ABC, AB = AC ABC is isosceles. If all the three sides of a triangle are equal, then it is an Equilateral Triangle. In ABC, AB = BC = CA ABC is equilateral.