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