Intercepts and the Cover-Up Method

Key Questions

  • What are the intercepts for horizontal and vertical line graphs?

    Answer:

    color(blue)("Horizontal line " x = a

    color(purple)("Vertical line " y = b

    Explanation:

    https://www.onlinemathlearning.com/forms-linear-equations.html

    Refer table above.

    "Equation of a line in" color(red)("Intercept Form") "is given by"

    x / a + y / b = 1, " where a in x-intercept and b the y-intercept"

    For a horizontal line, y = 0 or y/b = 0 and the equation becomes,

    x / a = 1 " or " x = a

    Similarly, for a vertical line, x = 0 or x / a = 0 and the equation becomes,

    y / b = 1 " or " y = b

    sankarankalyanam · 1 · Apr 14 2018
  • How do you use the cover-up method to solve for the x and y intercept?

    I suppose that "cover-up" is a friendlier term for "setting a variable equal to zero," so if you are looking for the x-intercept of a line, then set y equal to zero, and for y-intercept, set x-equal to zero.

    Example

    Let us find the x,y-intercepts of the line

    2x+3y=12.

    To find the x-intercept, set y=0.

    => 2x+3(0)=12 => 2x=12 => x=6

    So, the x-intercept is 6.

    To find the y-intercept, set x=0.

    => 2(0)+3y=12 => 3y=12 => y=4

    So, the y-intercept is 4.

    I hope that this was helpful.

    Wataru · 1 · Nov 2 2014

Questions

Graphs of Linear Equations and Functions