Answer:
The correct option is 1.
Step-by-step explanation:
If a quadratic equation is defined as
[tex]ax^2+bx+c=0[/tex]
then the quadratic formula is
[tex]x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}[/tex]
The given equation is
[tex]0=x^2-2x-3[/tex]
Here, a=1, b=-2 and c=-3.
Substitute these values in the above formula.
[tex]x=\frac{-(-2)\pm \sqrt{(-2)^2-4(1)(-3)}}{2(1)}[/tex]
[tex]x=\frac{2\pm \sqrt{(-2)^2-4(1)(-3)}}{2(1)}[/tex]
Therefore, the correct option is 1.
