Draw lines such as y = 2x + 3 using a table of values
Linear equations are always straight lines when you draw them, hence the word LINEar.
You can spot them because they only have an x term in them, and not x to the power of anything. So, x2 will not give you a linear eqation
Since linear equations are straight lines, they are very simple to do when you have to sketch a graph when working through worksheets or in your exam.
You need to know at least two sets of values (two points on the graph), then you just join them up with a ruler.
But to be more accurate, it is best to create a table of values with more than 2 points to draw the line.
This table will then tell you the x and y coordinates you need to plot, and then you just join them up with a ruler.
y = 2x + 4
Let's choose x = -2, -1, 0, 1, 2
x = -2
y =(2x-2)+4 = 0
x = -1
y =(2x-1)+4 = 2
x = 0
y = (2x0)+4 = 4
x = 1
y =(2x1)+4 = 6
x = 2
y = (2x2)+4 = 8
Which gives you 5 sets of co-ordinates to plot: (-2,0) (-1,2) (0,4) (1,6) (2,8)
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