Ahelicopter hovers 40 ft above the ground. then the helicopter climbs at a rate of 21 ft/s. write a rule that represents the helicopter's height h above the ground as a function of time t. what is the helicopter's height after 45 s

Since the rate is constant, the growth of the height of the helicopter follows a linear pattern. The helicopter has an initial quota of 40ft, so that would be the constant term. The linear terms's coefficient is the rate of growth, so 21 ft/s. So, if is the number of seconds passed from when the observation started, we have

Which means that, if , the height is

look a the sides they are perpendicular