Translations this from English to math
24 subtracted from the square of a number is x^2 -24 which is equal to 5 times a number (5x)
So we have x^2 -24 = 5x
x^2 -5x -24=0
(x-8) (x+3) = 0
x=8 x=-3.
The negative solution is -3
Lets check and see if this is right by substituting (-3) for x in our original equation
(-3)^2 -24 =5(-3)
9 -24 = 15
-15 = -15 so this answer is correct