 So in this video we're going to learn how to draw straight line graphs. In the process you're going to learn what I mean by table of values which will help you in future videos. You should already know about coordinates, axes and quadrants. If you have forgotten, watch our introduction to graphs videos first. So straight line graphs are found everywhere to make sure the right dose of medicine is given out throughout economics and in this video we're going to learn how to plot them. So we have this linear equation y equals 2x minus 3 but how do we plot it? It is actually really easy to do. So draw yourself a table of values like this and then we just need to substitute in some different values of x into the equation. I always start with 0. So substitute in 0 in place of x. So that means y equals 2 multiplied by 0 minus 3. So then y equals 0 minus 3. So y equals negative 3. And we can enter this into our table when x is 0, y is negative 3. So now choose another value of x. Keep the numbers small so let's go for x equals 1. So then y equals 2 multiplied by 1 minus 3. So y equals 2 minus 3 so y is negative 1. And again we can enter this into our table when x is 1, y is negative 1. So now it's your turn. Work out the remaining 3 y values for the corresponding x values. Pause the video, work out the answer and click play when you're ready to check. Did you get them right? 1, 3 and 5. So we now have 5 sets of coordinates. Wish we could just plot onto our graph. 0, negative 3, 1, negative 1, 2, 1, 3, 3 and 4, 5. So now we just need to join up our coordinates with a straight line using a ruler. Make sure you extend the line the whole way across the graph and label it with its equation. Simple, we plotted 5 coordinates but as a rule you need a minimum of 3 coordinates to accurately plot a straight line. We just had an extra 2 in case we made a mistake. Give this question a go yourself. Complete the table of values for this straight line. Pause the video, work out the missing values and click play when you're ready to check. Did you get the y values right? 7, 4, 1, negative 2 and negative 5. You should have just substituted in each value of x into y equals 7 minus 3x. So now we have our 5 coordinates, we can plot them straight onto our graph. And again join them up with a straight line and label it with its equation. So from this video you should be able to confidently plot any straight line onto a graph by substituting in different x values and having at least 3 coordinates. In part 2 we're going to look at what to do when we end up with fractions. It is a little bit more work but it's just as simple.