Triangles
A triangle has three sides and three angles
The three angles always add to 180°Equilateral, Isosceles and Scalene
There are three special names given to triangles that tell how many sides (or angles) are equal.
There can be 3, 2 or no equal sides/angles:
Equilateral TriangleThree equal sides
Three equal angles, always 60°
Isosceles TriangleTwo equal sides
Two equal angles
Scalene TriangleNo equal sides
No equal angles
What Type of Angle?
Triangles can also have names that tell you what type of angle is inside:
Acute TriangleAll angles are less than 90°
Right TriangleHas a right angle (90°)
Obtuse TriangleHas an angle more than 90°