Fortunately we are given the 2 zeros (-8 and 1) so (x-1) and (x+8) are factors
so we can write this as a(x-1)(x+8) = a(x^2 +7x -8). We can use the point (2,3) to solve for a
3= a( (2)^2 +7(2) -8))
3= a(4+14-8)
3= 10a
a=3/10
So our equation is
f(x)= (3/10)(x^2 +7x -8)
If you graph this equation you will see it passes through the 3 given points