1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: How would I graph this in my TI-83?

  1. Aug 17, 2011 #1
    1. The problem statement, all variables and given/known data

    |y| = 7-x

    The closest I can do is y=abs(7-x), but this just gives me a straight line along the y axis. Thank you for your time.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Aug 18, 2011 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    In this case x is a function of y, rather than y being a function of x.

    You can either:
    (1). Graph x on the vertical axis & y on the horizontal axis by switching x & y in your equation, then solve for y.

    (2). Do a parametric plot: Let yt = t and xt = 7 - abs(t), because x = 7 - |y|. Have t go from -20 to 20.​
  4. Aug 18, 2011 #3


    User Avatar
    Homework Helper

    You could graph two lines: y = 7 - x and -y = 7 - x [better known as y = x - 7]

    This would give to two intersecting lines making a large X

    You only want two if the branches.

    You want either the V, the inverted V [can't type it upside down] or the left hand two [>] or the right hand two [<].

    You could test the original expression by chosing a known point on each of the sections, to check which two you want, if you can't think of any other way of doing it.
  5. Aug 18, 2011 #4
    Ah. THank you guys. I wish I thought of those methods.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook