Answer:
[tex]f(x) = {x}^{2} - 4x + 4[/tex]
for zeros, f(x) = 0
[tex]f(x) = (x - 2) {}^{2} \\ {(x - 2)}^{2} = 0 \\ x - 2 = 0 \\ x = 2[/tex]
The zero is 2