If the coefficient of middle terms in $(1+\alpha x)^4$ and $(1-\alpha x)^6$ is same then $\alpha =?$

Question

$\begin{array}{1 1} -\large\frac{5}{3} \\ -\large\frac{3}{10} \\ \large\frac{5}{3} \\ \large\frac{10}{3} \end{array}$