# FORM FOUR MATHEMATICS STUDY NOTES TOPIC 3:THREE DIMENSIONAL FIGURES

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THREE DIMENSIONAL FIGURES

Three Dimensional Figures
Sometimes before you make any purchases you may want to know for example, how much cloth you need to make a pillow cover. What about a cover for your mattress or sofa cushion? How much oil paint do you need to paint your drinking water tank?
What about the amount of cloth for the pocket covers of your radio, curtain, suit, gown, trousers, set of table clothes, etc.
Answers to such questions and of the kind leads you to think more carefully about the size of the surfaces (faces) to be covered or coated on the bodies at work. Perhaps you need to take some measurements on the surfaces.
The knowledge of the surface areas of such bodies will enable you to choose or purchases the required amount without unnecessary wastage so as to minimize purchases costs too.
Three Dimensional Figures
Classify three dimensional figures
Three‐dimensional objects are the solid shapes you see every day, like boxes, balls, coffee cups, and cans.
It is called three-dimensional or 3D because there are three dimensions: width, depth and height.
-The following table shows examples of some common three dimensional figures
The Characteristics of Each Class
List the characteristics of each class
Here are some helpful vocabulary terms for solids:
Base: Is the bottom surface of a solid object.
Edge: Is the intersection of two faces on a solid object. This is a line.
Face: Is a flat side of a 3‐dimensional object.
Prism: Is a solid object with two congruent and parallel faces.
Pyramid: Is a solid object with a polygon for a base and triangles for sides.