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
x^2 - 2x + 1 = 0
(x - 1) (x - 1) = 0
This has a repeated root of 1
+1911 
