has three angles
The sum of all internal angles of a triangle is always equal to 180°
has three vertices
Equilateral Triangle
polygon
Acute Angled Triangle
The side opposite to the largest angle of a triangle is the largest side
Any exterior angle of the triangle is equal to the sum of its interior opposite angles
Isosceles Triangle
Obtuse Angled Triangle
The sum of the length of any two sides of a triangle is greater than the length of the third side
Right-Angled Triangle
Scalene Triangle
has three sides