I'm using Microsoft Office Excel 2007 for some statistics work for school. I made a linear trendline on a graph corresponding to a data set. This is what it looks like:
The data set in question is 4pcmm. All looks well.
However, the equation of the trendline is off. For example, if we calculate it at an X position of 50:
y = (4538.1 * 50) + (1 * 10^6)
Punch this into Excel (or just a calculator) and we get 1,226,905. However the graph clearly shows that at 50, the line is above 1,600,000. Hell, the line never even goes below 1,400,000.
So what's going on? Have I screwed something up or is it Excel which is at fault? And how do I fix this?