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Lines

There are two sorts of lines that are used to make shapes.

These are curved lines.

These are straight lines.

A two-dimensional or 2D shape is made up of lines. Sometimes the lines are curved and sometimes the lines are straight.

The lines all join up to make shapes like these.

What are sides?

When the lines join to make a shape they are not called lines, they are called sides.

Some shapes are made from only straight sides.

Some shapes are made from only curved sides.

Some shapes have a mixture of curved and straight sides.

Have a look around.

• Can you see any shapes that use straight lines?

• Can you see any shapes with curved lines?

Why not try drawing a picture using only straight lines.

Triangles

A triangle has 3 sides and 3 vertices (corners). A vertex is where two lines meet or join.

There are different kinds of triangles.

These triangles have sides that are all the same length.

These triangles have sides that have two different lengths.

Can you spot which sides are the same on each of the triangles?

These triangles have sides that are all different lengths.

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