One of the five quadratics below has a repeated root. (The other four have distinct roots.) What is the repeated root?
x^2 - 2x + 1
x^2 - 4x - 4
x^2 + 6x - 9
x^2 + 26x + 25
x^2 - 5x + 4
x2 – 2x + 1 has a repeated root. Factor to (x – 1)(x – 1)
or another way of saying that is (x – 1)2 and the root is 1.
edited to add: The root is 1 if x2 – 2x + 1 equals zero.
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+1678 
