What the answer to this

Answer:
(4, -15) is the vertex, a
Step-by-step explanation:
y=x^2-8x+1
-b/2a=x
y = ax^2 + bx + c
a=1 b=-8 c=1
x=8/2(1)
x=8/2
4 is the x of the vertex
y=4^2-8(4)+1
y=16-32+1
y=-15
(4, -15)
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