Which of the following is true for the relation f(x)=5x+1 a) both the equation and its inverse are functions b) only the equation is a function c) only the inverse is a function d) neither the equation nor it's inverse is a function

Answer is    a) both the equation and its inverse are functions======the relation    f(x) = 5x + 1is a linear function, so f(x) is a function.linear functions are one-to-one functions.because it is a one-to-one function, its inverse relation is a function.======alternatively, the  inverse of f(x) can be found algebraically. from it, we will be able to deduce that the inverse of f(x) is a function.if we replace f(x) with y    then interchaning the x and y (swapping them) will create the inverse.    then we solve for y to get an explicit equation for this inverse.    replace y with inverse notation and we get    the inverse is also a linear function, therefore it the inverse is a function.