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Working out the intercept of the Y-Axis

  1. Dec 13, 2007 #1
    If a gradient of -578.947 is present on a line of best fit then how can you work out the intercept of the Y-Axis when a co-ord of:

    (0.00000227, 0.00100) is given?

    Thank you
  2. jcsd
  3. Dec 13, 2007 #2


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    Well, a line is usually given by the equation y=ax+b, and the y-intercept i.e, the value of y when x=0 is evidently y=b.

    Having given coordinates (X,Y) of some point, you know that:

    Y=aX+b. Determine what a and b is from this.
  4. Dec 14, 2007 #3


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    A line with slope m, passing through [itex](x_0,y_0)[/itex] has equation [itex]y= m(x-x_0)+ y_0[/itex]. Put x= 0 and you have [itex]y= y_0- mx_0[/itex].
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