Types of Triangles
Types of triangles by its interior angles (acute triangle, right triangle, obtuse triangle) and by its sides(scalene triangle, isosceles triangle, equilateral triangle).
By Its Interior Angles
its interior angles are all acute angles.
0 < m∠(purple) < 90
it has a right angle.
m∠(blue) = 90
the sides that are adjacent to the right angle
the side that is opposite to the right angle
it has an obtuse angle.
90 < m∠(red) < 180
By Its Sides
it has no congruent sides.
it has two congruent sides (& angles).
the side that is adjacent to both congruent angles
it has three congruent sides (& angles).