Hector and Linh are working individually on a problem involving the function f(x) = x^2 -5.
On a domain where f is invertible, Hector says that f^-1(4) = 3, and Linh says that
f^-1(4) = -3
Is Hector correct? Is Linh correct? Justify your answer.

Ametal rod needs to be 9 feet and 5.5 inches in length. the sections of the poles being used are each 1 foot and 10.5 inches long. how many 1ft 10.5in sections would be needed to complete the 9ft 5.5in metal rod? and how many inches of material will be left?