Question 574691
You need to find a number that would make the denominator is 0, so you need to solve (x^2-4x+4) to be 0, then just plug in your answer and check to make sure that it is equal to 0.

{{{x^2-4x+4=0}}}
{{{(x-2)^2=0}}}
x-2=0
x=2