Could anyone give me a link to a good description or a description on how to do this?
Use the given values to find an equation of the form f(x)=ax^2+bx+c
1.f(0)=5, f(1)=10, f(2)=19
$\displaystyle f(0) = a(0)^2+b(0)+c = 5 $
$\displaystyle \therefore c = 5 $
$\displaystyle f(1) = a(1)^2+b(1)+c = 10 $
$\displaystyle a+b+5 = 10 $
$\displaystyle a+b = 5 $ ************
$\displaystyle f(2) = a(2)^2+b(2)+c = 10 $
$\displaystyle 4a+2b+5 = 10 $
$\displaystyle 4a+2b = 5 $ **************
You know c, and you now have two equations in a and b which you can solve simultaneously.