what is the side length of the square?

Question

After plotting the data where x=area, and f(x)=the length of one side of the square, Sam determined the appropriate model to approximate the side of a square was  Use the model Sam created to predict the side length of the square when the area is 14.

Answer 1

f(14) = √(14 + 2) - 1

f(14) = √16 - 1

f(14) = 4 - 1

f(14) = 3

Answer 2

approximate the side of a square was  

Area of a square = square of one of the side of a square

Then Area = [ √(x+2) -1 ]² = (x+2) - 2[ √(x+2) -1 ] + 1 = 14

This gets very difficult to type in, and I graphed it finding that x = 20.48