2. Copy the Cartesian plane opposite into your copybook, and plot (draw) points using the coordinates listed below. Label your points with the letters given. The fi rst one has been completed for you.
(i) A = (4, 2) (ii) B = (2, –4) (iii) C = ( –6, 6) (iv) D = (–7, –4)
(v) E = (–6, 0) (vi) F = (0, –8) (vii) G = (0, 0) (viii) H = (–3, –7)
–10 –8 –6 –4
y
6 4 2
–2 0
–4 –2
–6 –8
2 A = (4, 2) 4 6 8 10 x
1.3
Introducing area and perimeter of basic shapes on the Cartesian plane
Area of a shape
The area of a fl at or plane fi gure (shape) is the number of unit squares that can be contained within it.
The unit square is usually a standard unit, e.g. square units, a square metre, a square centimetre. How to fi nd the area of a regular shape using the coordinate plane
Worked example 1 Find the area of the rectangle made by the following points on the Cartesian plane.
A = (2, 5) B = (7, 5) C = (7, 2) D = (2, 2) Solution
By the end of this section you should be able to: ● fi nd the area of a regular shape ● fi nd the perimeter of a regular shape
● break up combined shapes into simpler shapes, and fi nd the total area and perimeter of these shapes
Section A Introducing concepts and building skills