f(x) is the same as y-values, and x is the same as the x-values on a coordinate grid because x is the independent variable, meaning y is the dependent variable, where f(x) depends on the value of x to find y.
So if y is -3, it can be found on the graph on the 4th line, so x = -1 when y = -3
When there are variables with exponents on the bottom you have to subtract the ones on the bottom from the ones on the top. Then if the exponent is negative you have to flip it.
