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: Straight line equation easy question

  1. Mar 31, 2010 #1
    i have an easy question i Know how to calculate the slope but how I can get all the equation I know before that the equation is -2x+2 I know how to calculate the slope it
    is y2-y1/x2-x1 but how can I get +2
    I attach a file describing the question
     

    Attached Files:

    Last edited: Mar 31, 2010
  2. jcsd
  3. Mar 31, 2010 #2
    The constant is the same as the point where the line crosses the y-axis. So in this case you see it crosses at positive 2 so the constant will be +2.
     
  4. Mar 31, 2010 #3
    your question is somewhat confusing...if you are asking how to get a slope = 2, you need a different line. the slope of a straight line is constant. y = -2x +2 is a straight line and you calculated the slope correctly, -2.

    To find a line with slope = 2, use slope equation...y=mx+b.
     
  5. Mar 31, 2010 #4
    It's not confusing if you look at the picture
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook