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I'm stuck with a chemistry problem as I did not have any statistics course so far and don't really understand the explanations I found online.

It's about dating rock and I'm supposed to use the least-squares method to calculate the slope and intercept of a linear isochron.

I can solve the problem with any given pair of data, but my results differ quiet a lot when I try to use a least-squares method as described on different websites (so I probably don't understand it, which also shows as I don't quiet know what the result actually represents)

Here's a rather random set of data

x - y

700 - 17

40 - 2

100 - 3

150 - 4

further given:

slope m=e^(labda t) - 1

and

t=(1/labda)ln(m+1)

labda = 1.4x10^-11

Any help is greatly appreciated

lil'me

edit: I know that I get the slope as one result and can calculate the time with it. I also know how to calculate the intercept if y=mx+b and mx being the slope and b the intercept. I just don't know which figure to use for y.

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# Least-squares problem

Can you offer guidance or do you also need help?

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