Please help !! i need help

Answer:
(x -10)/7
Step-by-step explanation:
As with division of numerical fractions, you can do it by multiplying by the inverse of the divisor. Similarly, as with division of numerical fractions, when the denominators are the same, the quotient is the ratio of the numerators.
[tex]\dfrac{x-10}{35x +21}\div\dfrac{7}{35x +21}=\boxed{\dfrac{x-10}{7}}[/tex]