We can use distribution property to multiply the polynomial by the monomial.
$$ \begin{aligned} \color{blue}{157320x} \cdot \left( 2x+5 \right) &= \color{blue}{157320x} \cdot 2x + \color{blue}{157320x} \cdot 5 = \\ &= 314640x^2+786600x \end{aligned} $$