Answer:
x = -2, 6
Step-by-step explanation:
You want the solution to x² -4x -12 = 0 using the quadratic formula.
The quadratic formula tells you the solutions to ax² +bx +c = 0 are ...
[tex]x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
In the given equation, the coefficients are ...
Using these values in the quadratic formula, we find the solutions to be ...
[tex]x=\dfrac{-(-4)\pm\sqrt{(-4)^2-4(1)(-12)}}{2(1)}=\dfrac{4\pm\sqrt{16+48}}{2}=2\pm4\\\\x\in\{-2,6\}[/tex]
The solutions to the quadratic equation are x = -2 and x = 6.