1. The problem statement, all variables and given/known data Find the rate of change of the area of a square whose side is 8 cm long, if the side length is increasing at 2cm/min 2. Relevant equations A(t) = xy x(0)=8 y(0)=8 dx/dt=2 dy/dt=2 3. The attempt at a solution dA/dt = dx/dt * x * dy/dt * y Using the product rule... dA/dt = dx/dt * x * y + dy/dt * y * x What happens now? Does the dx/dt * x = 1? or is it.. dA/dt = dx/dt * d/dx * x * dy/dt * d/dy * y Using the product rule.. dA/dt = dx/dt * d/dx * x * y + dy/dt * d/dy * y * x Therefore the d/dx = 1, therefore.. dA/dt = dx/dt * y + dy/dt * x dA/dt = 2*8 + 2*8 dA/dt = 32 cm^2/min ?? If it is correct is what I'm thinking correct (ie my working?) Help, thanks!