Identify 2D Shapes

How to identify 2D shapes

When you are asked to identify a 2D shape, look at the object’s flat outline and match its properties to a known shape. A 2D shape has only length and width, not depth.

1. Count the sides

Start by counting the straight edges.

• 3 sides → triangle
• 4 sides → square, rectangle, rhombus, or other quadrilateral
• 5 sides → pentagon
• 6 sides → hexagon

2. Look at the angles and side lengths

Use the shape’s details to narrow it down.

• All sides equal and all angles right angles → square
• Opposite sides equal, four right angles → rectangle
• Four equal sides, not necessarily right angles → rhombus
• Three sides → triangle, but check whether it is equilateral, isosceles, or scalene if needed

3. Check the overall outline

Some shapes are identified by their special features, such as:

• curved sides or corners,
• equal side patterns,
• symmetry,
• number of vertices.

4. Simplify your answer

If the question asks for the final shape name, write the standard geometric name only. Do not add extra words unless asked.

Quick check

Make sure your answer matches the number of sides and key properties. If two shapes seem possible, reread the side and angle clues before choosing.