How do you graph the line #y=2x+2#?
The minimum number of points needed to draw a strait line graph is 2. However, 3 is better as one of them forms a check. They should all line up. If not then something is wrong.
Lets determine 2 points
The line will 'cross' the y axis at
So we can determine these points (intercepts) by substitution.
For y-intercept set
So y-intercept is at the point
For x-intercept set
Divide both sides by
So the y-intercept is at the point
Mark and label these two points then draw you line through them. Take the line to the edges of the graphing area on the paper.
Do not forget to label your graph.
In an exam you get extra marks for labelling you points and giving a title to your graph.