x=4
Explanation
[tex](x-4)(x-4)=0[/tex]Step 1
solve for x means you have to find one or more values for x that satisfies the equality, so
[tex]\begin{gathered} (x-4)(x-4)=0 \\ (x-4)^2=0 \end{gathered}[/tex]so, to make the left side equal to zero
[tex]\begin{gathered} (x-4)^2=0 \\ square\text{ root in both isdes} \\ \sqrt{(x-4)^2}=\sqrt{0} \\ x-4=0 \\ \text{add 4 in both sides} \\ x-4+4=0+4 \\ x=4 \end{gathered}[/tex]therefore, the answer is
x=4
I hope this helps you