X = [1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20] Y = [1 1 4 5 6 7 8 8 9 9 12 11 12 13 14 17 18 17 20 19] a. Using the least squared regression formula find the equation of the regression line b. Find the regression line using polyfit and polyval Make sure to plot the regression line and the plot containing the original X and Y in the same graph.