Answer:
[tex]f(x) = (x-1)^2-6[/tex]
Step-by-step explanation:
Rewrite the quadratic using the method of completing the square:
[tex]x^2-2x-5=(x^2-2x+1)-1-5=(x-1)^2-6\\f(x) = (x-1)^2-6[/tex]
From this form it is immediately clear that the vertex of the parabola is at x=1 and its y-intercept at -6.