Explanation:
We can find the x-value of the vertex of the quadratic function y = x^2 + 2x - 24 by first finding the zeros of the function using the quadratic formula:
x = (-b ± sqrt(b^2 - 4ac)) / 2a
where a = 1, b = 2, and c = -24. Plugging in these values, we get:
x = (-2 ± sqrt(2^2 - 4(1)(-24))) / 2(1)
x = (-2 ± sqrt(100)) / 2
x = (-2 ± 10) / 2
So the zeros of the function are x = -6 and x = 4.
The x-value of the vertex is the midpoint between the zeros, which is simply the average of the two zeros:
x = (-6 + 4) / 2
x = -1
Therefore, the answer is B. -1.