30 lines
1.0 KiB
Markdown
30 lines
1.0 KiB
Markdown
---
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title: Point Slope Equation of a Line
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---
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## Point Slope Equation of a Line
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Point-slope is the general form y-y₁=m(x-x₁) for linear equations.
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It emphasizes the slope of the line and a point on the line (that is not the y-intercept).
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![point slope equation](https://www.mathsisfun.com/data/images/graph-point-slope-a.gif)
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## Derivation
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Any two points on a line A(x,y) and B(x₁,y₁) will always be on the same slope. A is assumed to be an arbitrary point on the same line.
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'm' is defined as the slope of the line and the tangent of the angle the line makes with the positive x-axis.
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Slope of a line between two points is given by:
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m = (y - y₁) / (x - x₁)
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for this case, where m is the slope of the line
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simplifying we get
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y-y₁=m(x-x₁)
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#### More Information:
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<!-- Please add any articles you think might be helpful to read before writing the article -->
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-[Khan Academy : Point slope equation](https://www.khanacademy.org/math/algebra/two-var-linear-equations/point-slope/v/idea-behind-point-slope-form)
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