so, the +/- means there are two answers, one that adds the √(-24) and one that subtracts the √(-24). You can leave that the way it is as +/-
The negative inside the square root is an imaginary number "i" = √(-1)
This is whats called a complex number which has the imaginary number "i".
Factor out the imaginary number and any perfect square factors of 24.
24 = 6 × 4
4 is a perfect square of 2, so 2 factors out of the square root.
-1 +/- √(-24)
-1 +/- i√(6×2²)
-1 +/- 2i√(6)
