Answer:
using 9 instead of √9
Step-by-step explanation:
The order of operations requires you to evaluate the radical contents, then the root, before the addition and division outside the radical. When you do that, you get ...
[tex]x=\dfrac{5\pm\sqrt{5^2-4(1)(4)}}{2(1)}\\\\x=\dfrac{4\pm\sqrt{9}}{2}\\\\x=\dfrac{5\pm3}{2}=\dfrac{\{8,2\}}{2}\\\\x=4,1[/tex]
The mistake was not taking the square root.
