x=1, y=25x=17, y=1Step 1: Calculate the common difference (d)d = (y(17) - y(1)) / (17 - 1) = (1 - 25) / 16 = -24 / 16 = -1.5Step 2: Write the equation of the arithmetic sequencey(x) = y(1) + (x - 1) * dStep 3: Substitute the values for y(1) and d into the equationy(x) = 25 + (x - 1) * (-1.5)Step 4: Use the Excel formula to calculate the sequence values=25+(B2-1)*(-1.5)