The first one can be put in as into the calculator

The second one is no good with a calculator because there are two variables. Sketch it by hand and you can find intercepts that depend on the value of a (y=0 at x=a,-a and x=0 when y=a). You can find the domain by making sure the what is under the radical is and you can find the range by solving the equation for x, and then finding the domain of that new function (you are finding the domain of the inverse function)