(t - 5)^2 - 4t * (-10 - 2t) = t^2 - 10t + 25 + 4t * 10 + 4t * 2t = t^2 - 10t + 25 + 40t + 8t^2 = t^2 + 8t^2 - 10t + 40t + 25 = 9t^2 + 30t + 25.
(t - 5)^2 - 4t * (-10 - 2t) = t^2 - 10t + 25 + 4t * 10 + 4t * 2t = t^2 - 10t + 25 + 40t + 8t^2 = t^2 + 8t^2 - 10t + 40t + 25 = 9t^2 + 30t + 25.