Intermediate Algebra for College Students (7th Edition)

$\dfrac{2}{3x}$
Given: $\dfrac{2}{9x}+\dfrac{4}{9x}$ Since,in the given rational expressions denominator are same, thus take it as common and add the rational terms simply. Thus, $\dfrac{2}{9x}+\dfrac{4}{9x}=\dfrac{2+4}{9x}$ or, $=\dfrac{6}{9x}$ or, $=\dfrac{2}{3x}$