10. The solution set of the inequality $\sqrt{a x+b}>x \quad(a>0, b>0)$ is
10. $\left[-\frac{b}{a}, \frac{1}{2}\left(a+\sqrt{a^{2}+4 b}\right)\right)$

From the graph, the solution set is $\left[-\frac{b}{a}, \frac{a+\sqrt{a^{2}+4 b}}{2}\right)$.