Answer:
[tex]x = \sqrt{24} - \frac{5}{2}\\ x =- \sqrt{24} - \frac{5}{2}[/tex]
Step-by-step explanation:
[tex]x^2+5x-24=0\\x^2+2.x.\frac{5}{2} + \frac{5^2}{2^2}-\frac{5^2}{2^2}=24\\ \\(x+\frac{5}{2})^2=24\\ x+\frac{5}{2} = \sqrt{24}\\ x+\frac{5}{2} = -\sqrt{24} \\[/tex]