Shape and Space 3

1
Shape and Space 3

• Area and Perimeter
• Qualifying to Teach standard2.1b

2
Objectives

• To develop subject knowledge of area and
  perimeter.

• To find the area and perimeter of 2D shapes.

3
Area
Area is a measure of the amount of
two-dimensional space inside a boundary.
Perimeter
Perimeter is the length of the boundary.
Think of fields and fences. The area is the size
of the field and the perimeter is the amount of
fencing around the edge.
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Area and Perimeter of a Square
b base
h height
Area h x b
Perimeter 4 x h (or 4 x b)
Remember in a square b h, because it all sides
are of equal length.
5
Area and Perimeter of a Rectangle
b base
h height
Area h x b
Perimeter (2xh)(2xb)
Remember in a rectangle opposite sides are of
equal length.
6
Area and Perimeter of a Right Angled Triangle
h height (perpendicular), b base, a
hypotenuse
Area ½b x h
Perimeter h b a
7
Area and Perimeter of a Triangle
h height (perpendicular), b base
Area ½b x h
Perimeter b (2xa)
Please note that if this was an equilateral
triangle (all sides the same length) the a b.
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Units of Area
9
Find the Area and Perimeter of the Following
1.5cm
10
Find the Area and Perimeter of the Following
9cm
18cm
21cm
5cm
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Find the Area and Perimeter of the Following
12
Now find the Area and Perimeter of the shapes on
the handout.
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Reading

• Chapters 11 from Mathematical Knowledge for
  Primary Teachers by J. Suggate, A. Davis and M.
  Goulding.
• Chapter 26 from Mathematics Explained for
  Primary Teachers by D. Haylock.