Final answer:
The vertex of the absolute value function f(x) = 5|x - 10| + 3 is at the point (10, 3).
Step-by-step explanation:
The vertex of an absolute value function of the form f(x) = a|x - h| + k is at the point (h, k). In the given function f(x) = 5|x - 10| + 3, the h value is 10 and the k value is 3, so the vertex is at the point (10, 3). Therefore, from the given options, the correct answer is (a) (10,3).