Page 99 - Knowledge Organiser Yr9 24-25

Knowledge Base: Mathematics Topic 31 : Calculations with 3D Shapes Year 9 | Spring Term, 2nd Half
By the end of this topic you should be able to:
• Name and state properties of 3D shapes
• Find symmetry in 3D shapes
• Calculate the volume of a prism
• Draw the net of a prism
• Calculate the surface area of a prism
Language
Meaning
Example
Prism
A 3D solid with the same crosssection throughout its length.
Here is a triangular prism.
Face
A flat surface of a solid.
A cube has 6 faces, 12 edges and 8 vertices.
Edge
The line where two faces meet.
Vertex
A point where three of more edges meet.
Net
A 2D shapes that can be folded to form a 3D solid.
Here is the net for a cube.
Important things to remember:
1) Volume of a prism = Area of cross-section × length
2) Surface area of a prism = Sum of the area of all its faces 3) Draw the net of a shape from the bottom up
Worked examples
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