Finding the slope of a Beer's Law calibration curve from Excel

[physicsman2]

Homework Statement

I made a graph of Absorbance vs. Concentration from data I got in the lab.
I graphed it and now am trying to figure out how to find the slope of the curve.
It's supposed to be a Beer's Law calibration curve.

Homework Equations

The Attempt at a Solution

I used Excel and got y = 228.19x + .0369 as the trendline.
Would 228.19 be the Beer's Law slope I need to use to find the concentrations of other absorbances later in the lab? It seems too high, but I really need feedback fast, please. Thank you.

 

[chemisttree]

Yes, it's the slope. Make sure you have chosen x and y correctly, though.