Triangle and rectangle

After the circle and the square, we'll meet two more shapes — the triangle and the rectangle.

Triangle

A triangle has three sides and three corners. The word "tri-angle" comes from "three angles".

You can find a triangle:

on the roof of a house
in a slice of pizza
on a warning road sign
in half a sandwich cut diagonally

Triangles can look different — some have all sides the same, some have one long and two shorter sides. But they always have three corners.

Rectangle

A rectangle has four sides and four corners, just like a square. But it's different — it has two long sides and two shorter ones. It looks like a stretched square.

You can find a rectangle:

on a door
on a TV
on a book
on a wall map
on most paintings in a gallery

Square vs. rectangle

A great question — what makes a square different from a rectangle?

a square has all four sides the same length
a rectangle has two long sides and two short sides

Otherwise they're similar — both have 4 corners.

Try it yourself

draw a triangle — three strokes, three corners. Try different shapes too.
draw a rectangle — four strokes, two long and two short

Try the exercises

In Name the shape you'll learn to tell a triangle and a rectangle apart from the rest.

In Find the shapes try to find every triangle or every rectangle.

When that's flowing, see where shapes hide in the real world: Shapes around us.