write a basic equation

Question

Water in a bucket is 3 cm deep.  During a rainstorm the depth of the water increases at a rate of 2 cm per hour.  Write an equation to represent the relationship between the depth of water (d) and how many hours it has been raining (h)

Answer 1

Since it originally  has 3 cm of water and increases at 2cm per hour, the depth of water is d = 3+2h.