Which statement is true and what are the reasons

Which represents the inverse of the function f(x) = 4x? h(x) = x + 4 h(x) = x – 4 h(x) = x h(x) = x

The parabola x= √y-9 opens: a.)up b.)down c.)right d.)left

Consider the function represented by the equation 1/2 j + 1/4 k equals 3 which shows the equation written in function notation with j as the independent variable