- 1). You must have a simple equation that requires either the x- or y-axis to equal a constant number. For example, x = 5. Note that y is absent in this equation. Y is absent because this equation does not require the y-axis to be intercepted, so a point would not be plotted on the y-axis. Since x will never change its value in this equation, you essentially already have a solution. If x equals a constant number and there is no other information provided, then y = 0.
- 2). The equation x = 5 would create a vertical line, with a point plotted on the graph at (5,0). Plot this point on the graph. Draw your vertical line using a pencil and, if required, a ruler. This line will be remain parallel to the y-axis due to its constancy.
- 3). For a horizontal line, y would have a constant value and x would have no value. For example, y = 6. If no information on x is provided, then it will equal 0. Therefore, plot a point at (0,6). Draw your horizontal line with a pencil and ruler. Note that the horizontal line at y will always remain parallel to the x-axis, since the numbers for both the y- and x-axis remain constant.
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