Given:-
[tex]\text{vertex}=(2,-1),y-intercept=7[/tex]To find:-
The function.
So the formula is,
[tex]y=a\mleft(x-h\mright)^{2}+k[/tex]So substituting we get,
[tex]y=7(x-2)^2-1[/tex]So the value. we get,
[tex]\begin{gathered} y=7(x-2)^2-1 \\ y=7(x^2-4x+4)-1 \end{gathered}[/tex]Since the value of x is,
[tex]\begin{gathered} y=7x^2-28x+28-1 \\ y=7x^2-28x+27 \end{gathered}[/tex]So the value,
[tex]y=7x^2-28x+27[/tex]