Trend lines are a type of regression analysis, which is a way to study the relationships between variables. In the context of small business, trend lines are often used to show sales trends and can be ...

I have a set of data, which I charted and then used the 'add trendline' tool to get a decent 2nd order poly. fit with the equation: y = -3E-39x^2 + 4E-19x + 3.4212 However, when I type this equation ...