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7: Straight Lines

  • Page ID
    45194
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    • 7.1: Slope of a Line
      Recall that ordered pairs can be graphed as points in the rectangular coordinate plane. The slope (m) of a line (l) that passes through points (x1,y1) and (x2,y2) is m = rise/run= (y2−y1)/(x2−x1) where x2 ≠ x1.
    • 7.2: Parallel Lines
      In a coordinate plane, parallel Lines are lines that do not meet or intersect. They are always the same distance apart. Moreover, parallel lines have the same slope.
    • 7.3: Perpendicular Lines
      Two distinct lines l and q are perpendicular if their intersection form four right angles or angles with measure 90°. The slopes of the perpendicular lines l and q are negative reciprocals.
    • 7.4: Equations of Vertical and Horizontal Lines
      The equation of a vertical line is of the form x = c, where c is any real number. The vertical line will always intersect the x−axis at the point (c,0). The slope of a vertical line is undefined. The equation of a horizontal line is of the form y = k, where k is any real number. The horizontal line will always intersect the y−axis at the point (0,k). The slope of a horizontal line is zero.
    • 7.5: Forms of the Equation of a Line
      The previous section explained the equations of vertical and horizontal lines. Now discover three more forms of the equations of a line, namely, the Slope-Intercept Form, the Point-Slope Form, and the Standard Form.
    • 7.6: Applied Examples
      To better understand the concepts learned in this chapter, apply them to real-life situation and every day problems.


    This page titled 7: Straight Lines is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Victoria Dominguez, Cristian Martinez, & Sanaa Saykali (ASCCC Open Educational Resources Initiative) .