A rational equation is an equation that involves at least one rational expression, which is a fraction where the numerator and/or denominator are polynomials.

To find the common denominator, identify the least common multiple (LCM) of the denominators of the rational expressions involved.

An asymptote is a line that a graph approaches but never touches. It can be vertical, horizontal, or oblique.

To solve a rational equation, first find a common denominator, multiply both sides by it to eliminate the fractions, and then solve the resulting equation.

The vertical asymptote indicates the values of x where the function is undefined and the graph approaches infinity.

A function is undefined at points where the denominator of a rational expression equals zero.

The horizontal asymptote can be determined by comparing the degrees of the numerator and denominator polynomials.