This document contains 6 presentations on the topic of coordinates: 1. Positive coordinates and plotting points in a plane 2. Writing coordinates of points and identifying locations 3. Plotting straight lines by connecting points 4. Plotting curves by connecting points in a smooth curve 5. Finding the midpoint of a line segment by averaging the x and y coordinates 6. Three-dimensional coordinates by extending points into the z-axis

1. Unit 27
Coordinates
Presentation 1 Positive Coordinates
Presentation 2 Coordinates
Presentation 3 Plotting Straight Lines
Presentation 4 Plotting Curves
Presentation 5 Mid-Points of Line Segments
Presentation 6 Three-Dimensional Coordinates

2. Unit 27
27.1 Positive Coordinates

3.
D F
E
G
C
B
1 2 3 4 5 6 7 8 9
9
8
7
6
5
4
3
2
1
(a) Plot the points A(3, 8), B(6, 1) and C(2, 5)
A
(b) What are the coordinates of the following points
D (0, 5)
E (6, 3)
F (6, 5)
G (8, 0)
?
?
?
?
x
y

4. Unit 27
27.2 Coordinates

5. Write Down the coordinates for:
Lighthouse (7, 1) Shop (-4, 3)
Telephone Box (-4, 1) Jetty (2, 2)
Campsite (3, -4) Cafe (-5, -2)
On the grids above, what is at the point
A (4, -2) Church
B(-2, -3) Lifeboat Station
?
?
-8 -7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 8
Telephone Box
Campsite
Lighthouse
Church
Jetty
Cafe
Shop
Lifeboat
station
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
?
??
??
?
x
y

6. Unit 27
27.3 Plotting Straight Lines

7. (A) Complete the following pairs of coordinates for
(4, 2) (1, -1) (-1, -3)
(B) Plot these points on the grid below.
? ? ?
4
3
2
1
0
-1
-2
-3
-4 -3 -2 -1 1 2 3 4 5
(C) Draw a straight line through these points.
x
y

8. Unit 27
27.4 Plotting Curves

9. x -3 -2 -1 0 1 2 3
y 7 2 -1 -2 -1 2 7
?
(A) Complete the table below for the relationship
? ? ? ? ? ?
(B) Plot the points on the grid below, drawing a smooth curve
through them
7
6
5
4
3
2
1
-1
-2
-3
-6 -5 -4 -3 -2 -1 1 2 3 4
x
y
0

10. Unit 27
27.5 Mid-Points of Line
Segments

11. What are the coordinates of the mid-point of the line segment AB?
The coordinates of A are (2, 7) and of B (5, 3)
Hence the coordinates of the mid-point of AB are:
Show this point on the
diagram
?
7
6
5
4
3
2
1
-1
-2
-3
-4
-5
-6
-6 -5 -4 -3 -2 -1 1 2 3 4 5 6
?
? ?
? ??
D
C
A
B
x
y

12. What are the coordinates of mid-point of the line segment AC?
The coordinates of A are (2, 7) and of C (-5, 3)
Hence the coordinates of the mid-point AC are:
Show this point on the
diagram
7
6
5
4
3
2
1
-6 -5 -4 -3 -2 -1 1 2 3 4 5 6
D
C
A
B?
????
??
-1
-2
-3
-4
-5
-6
x
y

13. 7
6
5
4
3
2
1
-6 -5 -4 -3 -2 -1 1 2 3 4 5 6
D
C
A
B
What are the coordinates of mid-point of the line segment BD?
The coordinates of B are (5, 3) and of D (-4, -5)
Hence the coordinates of the mid-point BD are:
Show this point on the
diagram
?
-1
-2
-3
-4
-5
-6
?
? ?? ?
?
x
y

14. Unit 27
27.5 Three-Dimensional
Coordinates

15. z
H G
FE
D C
BA x
y
If AB = 6, AD = 5 and AE = 2, write down the coordinates of each
vertex of the cuboid
A (0, 0, 0) B (6, 0, 0)
C (6, 5, 0) D (0, 5, 0)
E (0, 0, 2) F (6, 0, 2)
G (6, 5, 2) H (0, 5, 2)
?
?
?
? ?
?
?
?