Equation of a Line
Equation of a Line
The various common forms for the equation of a line are listed below. In all forms, slope is represented by m, the x-intercept by a, and the y-intercept by b.
Note: The standard form coefficients A, B, and C have no particular graphical significance.
Forms for the Equation of a Line |
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| Slope-intercept | y = mx + b |
Used when you have the slope and the y-intercept. |
| Point-slope | y – y1 = m(x – x1) |
(x1, y1) is a point on the line. |
| Standard form | Ax + By = C |
If possible, A is nonnegative and A, B, and C are relatively prime integers. |
| Two-intercept |
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Used when you have both intercepts. |
| Vertical | x = a |
All points have x-coordinate a. |
| Horizontal | y = b |
All points have y-coordinate b. |
Movie Clips (with narration)
