A triangle is a shape that has 3 straight sides and 3 angles.
We have different names for different kinds of triangles.
Let's learn about three types of triangles, named based on the length of their sides.
A triangle in which none of the sides are equal is called a scalene triangle.
This is a scalene triangle. The three sides are not equal.
A triangle that has two equal sides is called an isosceles triangle.
This triangle has two sides that are the same length, 9.
An equilateral triangle has 3 equal sides.
So if one side is 7, we know that the other two sides are also 7.
The equilateral triangle is probably the most common. It's used on street signs.
Can you spot things around you that form an equilateral triangle?
Tip: Equilateral triangles always have three 60 degree angles.
The three types of triangles, defined by the length of their sides, are called scalene, isosceles, and equilateral.
Great job.
Now, try the practice to help you remember for longer.