2. An equilateral triangle has variable side length a such that the perimeter is a differentiable function of time. Which equation best describes the relationship between the rate of change, with respect to time t, of the perimeter P and the rate of change, with respect to time t, of the sides of the equilateral triangle?

answers:

dP/dt=-3da/dt

dP/dt=3da/dt

dP/dt=-3a da/dt

dP/dt=3a da/dt