View
214
Download
0
Category
Tags:
Preview:
Citation preview
• I can plot coordinates.• Given the equation of a straight line, I can complete a table
of values.• From a table of values, I can draw a straight line.• Given a set of data, I can plot points on a scatter graph.• I can draw a line of best fit.
S3 BLOCK 8 Straight Line
Coordinates
I can plot coordinates.
Review: Coordinates
Remember that the first number is the -coordinate and the second number is the -coordinate.
Along first, then up or down.
Example 1
(a) Plot the points (1, 2) (2,3) (3,4) (4,5) and (5,6).(b) Draw a straight line through these points.
Plot the points (1, 2) (2,3) (3,4) (4,5) (5,6)
Table of values
Given the equation of a straight line, I can complete a table of values.
From a table of values, I can draw a straight line.
Table of values
Complete the table below for
To do this, replace different values of into the equation
-2 -1 0 1 2
Replace then then then then then
-2 -1 0 1 2-1-3 1 3 5
Plot the points (-2, -3) (-1, -1) (0, 1) (1, 3) (2, 5)
A straight line can be drawn through these points
-2 -1 0 1 2-1-3 1 3 5
Scatter graph
Given a set of data, I can plot points on a scatter graph.
I can draw a line of best fit.
Scatter graphs
Scatter graphs are used to represent and compare two sets of data.By looking at a scatter diagram it is possible to say whether there is any connection (correlation) between the two sets of data.
Line of Best Fit
When there is a correlation between sets of data on a scatter graph, it is possible to draw a line of best fit.
When drawing a line of best fit the aim is to keep the distance of all the points from the line to a minimum.
Sometimes it is helpful to try to keep the number of points above the line as the same as the number of points below the line.
ExampleIn a class 10 pupils tool a Science test and an Maths test.Their scores are listed in the table.
(a) Illustrate this data with a scatter graph.(b) Draw a best fitting line on the graph
Pupil A B C D E F G H I JMaths Score 2 10 15 4 9 6 14 19 12 18Science Score 6 12 18 3 11 8 14 17 10 20
Scie
nce
Scor
e
Maths Score0 5 10 2015
0
5
10
15
20H
B
C
D
E
F
G
A
I
J
Scie
nce
Scor
e
Maths Score0 5 10 2015
0
5
10
15
20H
B
C
D
E
F
G
A
I
J
Recommended