Quick Graphs using Slope-Intercept form:

• X-intercept - the point where the line crosses the x-axis.
• Y-intercept - the point where the line crosses the y-axis.

How to Graph Using the x and y Intercepts

• Find the x-intercept.
  • Substitute zero in place of y in the equation.
  • Solve the equation for x.
  • You get the ordered pair (x, 0).
• Find the y-intercept.
  • Substitute zero in place of x in the equation.
  • Solve the equation for y.
  • You get the ordered pair (0, y).
• Graph the two intercepts or points.
• Connect the points with a straight line and arrows on each end.
• Label the line with its equation.

You do this by plugging in ANY three values for x and find their corresponding y values. It can be ANY three values you want, 1,-3, or even 10,000. Remember there are an infinite number of solutions. As long as you find the corresponding y value that goes with each x, you have a solution. Remember that each ordered pair corresponds to only one point on the graph. The point lines up with both the x value of the ordered pair (x-axis) and the y value of the ordered pair (y-axis).

A linear equation will graph as a straight line.

If you know it is a linear equation and your points don't line up, then you either need to check your math in step 1 and/or that you plotted all the points found correctly.

• Step 1

  Draw a pair of perpendicular lines. These are your axes (the plural of axis). Label the horizontal axis x and the vertical axis y Label several different values, both positive and negative, of x and y on both axes. This is the scale of the graph.

• Step 2

  Remember that your equation should be in the form y = mx + b (if it is in a different form, solve for y in terms of x).

• Step 3

  Draw a dot on the y axis at y = b. This is the y-intercept of the graph (the point at which the graph crosses the y-axis).

• Step 4

  Choose a value for x other than 0 and mark this on the x-axis you've drawn. Lightly draw a vertical line that crosses this value of x on your x-axis.

• Step 5

  Plug the x value you chose into your equation.

• Step 6

  Solve for y. Lightly draw a horizontal line that crosses this value of y on your y-axis.

• Step 7

  Make a dot where the two lines you just drew intersect.

• Step 8

  Draw a straight line between this dot and the y-intercept. Extend this line in both directions to the edges of your graph. This line is the graph of your equation.