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William
10-28-2013, 05:56 PM
If x^2-2x+1=0 , which of the following is the value of x-1?

(A) 0
(B) 1
(C) 2
(D) 3

Thanks!

Thomas
10-28-2013, 05:56 PM
First solve the quadratic equation

x^2-2x+1=0 \Rightarrow (x-1)^2=0 \Rightarrow x=1

and then plug in this value to the expression x-1=1-1=0

Therefore the correct answer is (A).

William
10-28-2013, 05:56 PM
First solve the quadratic equation

x^2-2x+1=0 \Rightarrow (x-1)^2=0 \Rightarrow x=1

and then plug in this value to the expression x-1=1-1=0

Therefore the correct answer is (A).


Thank you!