How to draw a graph of a linear equation

A linear equation is drawn as a straight line on a set of axes.
To draw the graph we need coordinates.
We generate these coordinates by substituting values into the linear equation.

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Find out how to draw a graph of a linear equation

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Click to see a step-by-step slideshow.
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YOU WILL NEED: A whiteboard. a ruler, pen and a piece of squared paper.
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STEP 1 - Draw a table of values for the x and y coordinates. Add the x coordinates 0, 1, 2, 3 and 4.
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STEP 2 - Using the equation y = 2x + 1, calculate the value of y by using the x value in the table. In this instance, x=0. Do the same for x=1, x=2, x=3 and x=4.
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STEP 3 - Draw a graph and label the x axis 1 to 4 and the y axis 1 to 9.
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STEP 4 - Plot the coordinates (0,1), (1,3), (2,5), (3,7) and (4,9).
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Step 5 - Draw a line through the coordinates plotted.
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Well done! You've drawn a line of the linear equation y = 2x + 1.

A linear equation is represented as a line graph. In order to draw the line graph we require several pairs of coordinates. These coordinates represent the relationship given in the equation.

For example, for y = 3x, the y value is always equal to '3 lots' of the x value. (1,3), (10,30) and (2.5,7.5) are all coordinates on the line y = 3x.

Often a table of values is used to create the coordinates. We use substitution to calculate the values.

For example y = 2x + 1

The y value is always '2 lots' of the x value plus 1.

We replace the value of x for different numbers and record the resulting y value.

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How to draw a graph of a linear equation

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More on Straight line graphs

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