Question

the sides of a square increase in length at a rate of 3 m/s. what rate is the area of the square changing when the sides are 30 m long?

Answer 1

First define the area of a square, then find the derivative of it to see how fast the area is changing. The given is that the sides are changing at 3 m/s, so you know there's a relationship now between the derivative and how fast the sides are changing

Answer 2

How do I go about doing that?

Answer 3

I'd probably go with A = s^2 then take d/dt to both sides, see if it starts to make more sense then.