Answer
$\dfrac{6}{7}$
Work Step by Step
RECALL:
$\dfrac{a}{b} \div \dfrac{c}{d} = \dfrac{a}{b} \times \dfrac{d}{c}$
Use the rule above to obtain:
$=\dfrac{3x}{5y} \times \dfrac{10y}{7x}$
Cancel out the common factors, and then multiply to obtain:
$\require{cancel}
\\=\dfrac{3\cancel{x}}{\cancel{5y}} \times \dfrac{\cancel{10y}2}{7\cancel{x}}
\\=\dfrac{3}{1} \times \dfrac{2}{7}
\\=\dfrac{6}{7}$
