Check the option to display equation on chart. Examine the equation for the line which Excel is now displaying overlaid on the scatter plot. To work out the polynomial trendline Excel uses this equation.
Write this formula in A10.
Where x bar is the mean of the know xs and y bar is the mean of known ys. One is graphically using the options of the trend line. SLOPE B2B7A2A7 Now in C2 write this formula and drag it down to C7. Recall that the R-squared value.