ANSWER
There are two solutions and they are both complex solutions. The solutions are:

Step-by-step explanation
We want to determine the number and nature of solutions to the equation:

To do this, solve the equation by first, finding the square root of both sides of the equation:
![\begin{gathered} \sqrt[]{(3a+24)^2}=\pm\sqrt[]{-36}=\pm\sqrt[]{-1\cdot36} \\ \Rightarrow3a+24=\pm\mleft\lbrace\sqrt[]{36}\cdot\sqrt[]{-1}\mright\rbrace \\ 3a+24=\pm6i \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/8pv8ysz8qoke8iex6dvswe5e53a4zq6u30.png)
Now, solve the equation for a:

Hence, there are two solutions and they are complex solutions.