#### Answer

$7x^{4}-4x^{2}+2$

#### Work Step by Step

Using the property: $\displaystyle \quad\frac{A+B}{C}=\frac{A}{C}+\frac{B}{C},$
$\displaystyle \frac{49x^{7}-28x^{5}+14x^{3}}{7x^{3}}=\frac{49x^{7}}{7x^{3}}-\frac{28x^{5}}{7x^{3}}+\frac{14x^{3}}{7x^{3}}$
$= 7x^{7-3}-4x^{5-3}+2x^{3-3}$
= $7x^{4}-4x^{2}+2$