Answer
$x=2$
Work Step by Step
Subtract $4x$ and add $4$ to both sides f the equation to have:
$x^2-4x+4=4x-4-4x+4
\\x^2-4x+4=0$
Factor the trinomial to have:
$(x-2)(x-2)=0$
Equate eachunique factor to zero then solve each equation to have:
$x-2=0
x=2$
Thus, the solution is $x=2$.