Final answer:
The quadratic function in standard form is -0.5(x - 8)^2 + 8.
Step-by-step explanation:
To write a quadratic function in standard form, we can start by finding the factors of the quadratic equation based on the given information.
The x-intercepts are -1 and 12, which means the factors would be (x + 1) and (x - 12).
The vertex is (8,8), so the equation would have the form a(x - h)^2 + k, where (h, k) is the vertex.
Substituting the vertex values, we get a(x - 8)^2 + 8.
Finally, we can use the point (4,0) to solve for 'a' and find the final quadratic function.
Using the point (4,0), we can substitute x = 4 and y = 0 in the equation a(x - h)^2 + k.
This gives us the equation a(4 - 8)^2 + 8 = 0.
Solving this equation, we find that a = -0.5.
So, the quadratic function in standard form that satisfies the given conditions is -0.5(x - 8)^2 + 8.