A hot-air balloon is 150 ft above the ground when a motorcycle (traveling in a straight line on a horizontal road) passes directly beneath it going 45 mi / hr (66 ft/ s). If the balloon rises vertically at a rate of 12 ft/s, what is the rate of change of the distance between the motorcycle and the balloon 7 seconds later? Let x be the horizontal distance from the balloon to the motorcycle, y be the vertical distance from the balloon to the road, and z be the distance between the motorcycle and the balloon. Write an equation relating x, y, and z. Differentiate both sides of the equation with respect to t. dx The rate of change of the distance between the motorcycle and the balloon after 7 seconds is about (Round to two decimal places as needed.)