Answer:
(-3,0) is the other x-intercept
Explanation:
We know that the equation for the vertex form of a parabola is y=a(x-h)^2+k where (h,k) is the vertex.
Given (h,k) -> (1,-16) then we have y=(x-1)^2-16 as our equation.
Given that one x-intercept is at (5,0) we can plug in y=0 to find both:
0=(x-1)^2-16
0=x^2-2x+1-16
0=x^2-2x-15
0=(x-5)(x+3)
x=5 and x=-3
Therefore, the other x-intercept is (-3,0)