TeX source:
\begin{array}{rcl}g'_x(x,y) &=& \dfrac{1}{2}x^{\frac{1}{2}-1}+5y+0 \\\\&=& \dfrac{1}{2}x^{-\frac{1}{2}}+5y \\\\&=& \dfrac{1}{2\sqrt{x}}+5y\end{array}