Answer:
x = 5
Explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
(h, k ) are the coordinates of the vertex and a is a multiplier
h(x) = 19(x - 5)² + 6 ← is in vertex form
with vertex (h, k ) = (5, 6 )
The axis of symmetry is a vertical line passing through the vertex
with equation x = 5