The first use of the spreadsheet in Problem A4 requires only the entry of data. To draw the graph for Problem A5, select the data, and then select the graphing tool (this is called the Chart Wizard if you're using Excel). The type of graph or chart for representing a functional relationship is an XY graph, or scatterplot. Some of the scatterplots will display only points, like this:
Others will connect the points with a line:
Groups: After creating the graphs, pause to discuss which graph was chosen to represent the function. Some may say that the points should not be connected because, in this context, the function makes sense only for whole numbers. For example, it may not make sense to talk about how many squares 4.5 toothpicks can make. It is often useful, however, to connect the points on a graph like this so that we can see the shape of the function (in this case, a straight line) more clearly. This is often done by indicating the actual data points by large dots or diamonds and then connecting them with a narrower line.
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