Question

A company makes computer chips from square wafers of silicon. It wants to keep the side length of a wafer very close to 12 mm and it wants to know how the area A(x) of a wafer changes when the side length x changes. Find A'(12)

Answer 1

The first part of the question asks for how the area changes with changes to the length of the side. The area will grow exponentially with the change of the length of the side, more specifically, to the second power. 
If the length is 2 the area is 4
If the length is 3 the area is 9
and so forth. 

If the length of the side of the wafer, x, is 12 the area would be 12(12)= 144 squared millemeters