Question 52345
You find x intercepts by letting y=0 and solving for x.  For this one let y=0, factor, then set each parenthese =0 and solve for x.
y=x^2-4x+4
0=(x-2)(x-2)
0=x-2
0+2=x-2+2
2=x
Since this is a perfect square trinomial, there is only one x-intercept.