Chapter 5
Linear Functions
By Boundless
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Linear functions are algebraic equations whose graphs are straight lines with unique values for their slope and y-intercepts.
Slope describes the direction and steepness of a line, and can be calculated given two points on the line.
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Two variables in direct variation have a linear relationship, while variables in inverse variation do not.
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A zero, or
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The slope-intercept form of a line summarizes the information necessary to quickly construct its graph.
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The point-slope equation is another way to represent a line; only the slope and a single point are needed.
Any linear equation can be written in standard form, which makes it easy to calculate the zero, or
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The distance and the midpoint formulas give us the tools to find important information about two points.
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Parallel lines never intersect; perpendicular lines intersect at right angles.
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A linear inequality is an expression that is designated as less than, greater than, less than or equal to, or greater than or equal to.