The 6 Types of Triangles By.Carter a right triangle is a triangle that has one 90 degree angle an acute triangle is a triangle that all angles are less than 90 degrees An obtuse triangle is a triangle with one angle that's more that 90 degrees but an Isosceles triangle is a triangle that has two equal sides and angles an equilateral triangle is a triangle that all sides are the same a scalene triangle is a triangle that has no angles and no sides the same