### The Line Defined

A linear equation is a special kind of function. Remember in the preceding section, when we defined a function by a set of ordered pairs or points? Each of those points is an **individual solution** for the equation y = 2x. The **complete solution** is all the points that satisfy the equation. If you began plotting individual solutions to a linear equation, an interesting pattern would emerge.

Look at the table for the linear equation y = 2x again. The table offers five individual solutions to the equation. Before you look at Figure 1.9, plot these five points and see if you can figure out the pattern. If you're not sure, try some additional solutions. As you plot more and more solutions, a line starts to emerge, as shown in Figure 1.9 ...

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