Question #N490
If $x^2 - 4x + 4 = 0$, what is the value of $x$?
A. -2
B. -1
C. 1
D. 2
Correct Answer is: D
The expression on the left-hand side of the equation is a perfect square trinomial: $(x-2)^2 = 0$. Taking the square root of both sides, we get $x-2 = 0$. Adding 2 to both sides, we find $x = 2$.