The solutions are:
[tex]\begin{gathered} x=48.13821001 \\ or \\ x=-48.47154335 \\ \text{Let's take the positive solution, } \\ x\approx48 \end{gathered}[/tex]Quadratic formula:
[tex]\begin{gathered} \text{Given a equation:} \\ ax^2+bx+c=0 \\ \text{The solutions for this equation can be found using this formula:} \\ x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ In\text{ the previous problem:} \\ a=0.003 \\ b=0.001 \\ c=-7 \end{gathered}[/tex]