Answer-
the standard form of the function is,
[tex]f(x)=-\frac{1}{2}x^2+6x+45[/tex]
Solution-
The standard form of the function is,
[tex]f(x)=ax^2+bx+c[/tex]
Taking the points as (0, 45), (2, 55), (4, 61)
Then putting (0, 45) in the equation,
[tex]\Rightarrow 45=a(0)^2+b(0)+c\\\\\Rightarrow c=45[/tex]
Then putting (2, 55) with the value of c in the equation,
[tex]\Rightarrow 55=a(2)^2+b(2)+45[/tex]
[tex]\Rightarrow 4a+2b=10[/tex] -------1
Then putting (4, 61) with the value of c in the equation,
[tex]\Rightarrow 61=a(4)^2+b(4)+45[/tex]
[tex]\Rightarrow 16a+4b=16[/tex] ------ 2
Solving equation 1 and 2, we get,
[tex]\Rightarrow a=-\frac{1}{2},\ b=6[/tex]
Putting the values of a, b, c in the standard form,
[tex]f(x)=-\frac{1}{2}x^2+6x+45[/tex]