You can put this solution on YOUR website! This problem can be factored using reverse foil.
I assume you know the foil method.
x^2-8x+16
(x-4)(x-4)
using foil you can check your answer.
first times first x^2
inside times inside -4x
outside times outside -4x
last times last 16
so you have x^2-8x+16.
your factors of (x-4)(x-4) check out correctly.
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