First, show you how to do linear regression in google docs (trendline). Second, I will show you how to do it the long way in google docs. It seems I did this before, but I just can't find it.

For a simple linear regression model, ... If any assumption such as linearity, independence of errors, or homoscedasticity are violated, RSS may lead to biased estimates and incorrect inferences.

The attenuation factors estimated in a linear regression calibration model were 0.368 (0.228, 0.508) for nitrogen and 0.500 (0.361, 0.639) for potassium intakes; only the former was different from ...