The domain of the function can be obtained by pluging the values of the range into f(x), i.e domain = {k^2 + 2k + 1 = 25, k^2 + 2k + 1 = 64} = {k^2 + 2k - 24 = 0, k^2 + 2k - 63 = 0}. Solving the two quadratic equations, we have that the range is {-9, -6, 4, 7}.I hope that my answer is helpful! Let me know if you need something more :)