To plot a straight line, create a small table.
Determine at least three values of x to plot, and work out the values of y using the equation. Plot the points, and draw a straight line through the three points, extending the graph beyond the two outside points.
If a straight line cannot be drawn through these points, check the calculations.
1. An equation is given by y = 3x - 4.
What are the coordinates that would be plotted for x = -2, x = 0 and x = 3?
Answer: (-2, -10), (0, -4) and (3, 5)
|3x - 4||-10||-4||5|
2. Plot the graph for y = 2x + 4.