A scalene triangle has no sides equal and no angles equal.
An isosceles triangle has two sides equal and also two angles equal.
An equilateral triangle has all three sides and all three angles equal to 60°.
A right-angled triangle is one in which one angle is 90°.
Examples:
Scalene | Isosceles | Equilateral | Right angle |
Note that equal sides are marked by small dashes.