To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $2\left(-x-2\right)$ and $4$ is $4\left(x+2\right)$. Multiply $\frac{3}{2\left(-x-2\right)}$ times $\frac{-2}{-2}$. Multiply $\frac{1}{4}$ times $\frac{x+2}{x+2}$.
Since $\frac{-4+x}{4\left(x+2\right)}$ and $\frac{-2x\times 4\left(x+2\right)}{4\left(x+2\right)}$ have the same denominator, add them by adding their numerators.
Apply the distributive property by multiplying each term of $-2x-\frac{1}{8}\sqrt{97}-\frac{15}{8}$ by each term of $x-\frac{1}{16}\sqrt{97}+\frac{15}{16}$.