The gradient of a line describes how steep the line is. In the figure, line
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The gradient of a line is defined as the ratio of the vertical distance to the horizontal distance. This can be understood by looking at the line as the hypotenuse of a right-angled triangle. Then the gradient is the ratio of the length of the vertical side of the triangle to the horizontal side of the triangle. Consider a line between a point
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So we obtain the following for the gradient of a line:
We can use the gradient of a line to determine if two lines are parallel or perpendicular. If the lines are parallel (Figure 3a) then they will have the same gradient, i.e.
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For example the gradient of the line between the points
The following video provides a summary of the gradient of a line.
| Gradient of a line |
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