Simplify rational expression

An algebraic expression where both the numerator and the denominator are polynomials e.g.


is called a rational expression. Since the denominator can't be zero there are values of x which are excluded from the rational expression. The expression above has an excluded value of zero.

To simplify a rational expression you have to eliminate all factors that are common of the numerator and the denominator. To accomplish this use the greatest common factor (GCF) of the factors e.g.

$$\frac{4xy}{6y^{2}}=\frac{2y\cdot x}{2y\cdot 3y}=\frac{{\color{red} {\not}{2y}}}{{\color{red}{ \not}{2y}}}\cdot \frac{x}{3y}=\frac{x}{3y}$$

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Simplify rational expression