For the inverse of a quadratic function, you must complete the square if necessary, then you can combine the x and x^2 terms into a
(x+?)^2 term, take the square root of both sides etc...
For rational functions, it is sometimes helpful to multiply both sides by the denominator of the x term, multiply y and the denominator through, get all the x terms on one side and solve for x. If you have to combine x^2 terms with x terms, complete the square. If x is cubic or above, it can get tricky
