I will not work this problem for you, but I will tell you how to do it.
The equation you want is Ax2 + Bx + C = y
Put each pair of (x,y) values into the equation.
You will get 3 simultaneous linear equations in the unknowns A, B and C.
Solve the simultaneous set and you will have your answer. The set will not be too messy because you will be able to eliminate C easily!