For just 3 but if you know 4 also then it’s on my page and i would appreciate the

A quadratic equation is set up in the form of ax² + bx +c
First set equation = to 0
0= x² - 5x - 24
Next plug into quadratic formula( -b Plus or minus the √b²-4ac) ÷ 2a
[10 plus or minus √(25² - 4×1×24)] ÷ 2
Solve for inner parenthesis first 
√625- 96   = √529
Now set up two equations
(10 + √529) ÷2   = x   = 16.5
(10 -  √529) ÷2   = x   = -6.5 
So therefore x = 16.5 and -6.5