The standard form of a quadratic equation is: ax²+bx+c=0, and it is represented with a polynomial of degree 2, that's why it is also called "Equation of degree 2".
1. So, if 3 and 8 are zeros of the quadratic function, then they are factors of it. Therefore, you have:
(x+3)(x+8)=0
2. When you write it in the standard form, you have:
x²+11x+24=0
a=1
b=11
c=24