title: Extract data from plot in r
body: <p>I have made a plot using ggplot on R and using the function <code>nls</code> because it was a non linear regression, now I would like to extract data from the graph, specifically I would like to know the value of the 2 curves in the graph when the y value is 0, and I have to do it using R..</p>
  
  <p>Is it possible?</p>