## Elementary Algebra

$= \frac{4x}{9}$
In order to solve, first multiply the fractions together. Then, cancel out common factors in the numerator and the denominator of the fraction to obtain: $= (\frac{7x^{2}}{9y})(\frac{12y}{21x})$ $= \frac{84x^{2}y}{189xy}$ $= \frac{4x}{9}$