Question 172668
write the quadratic function in vertex form. Then, identify the vertex. 
x²-16x+56=y
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x^2 - 16x + ? = y-56 + ?

x^2 - 16x + 64 = y-56 + 64

(x-8)^2 = y+8
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Vertex: (8,-8)
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Cheers,
Stan H.