Question

value of 18= Z-9 what I need to do?

Answer 1

we need solve z

$\begin{gathered} 18=Z-9 \\ 18+9=Z-9+9 \\ 27=Z+0 \\ Z=27 \end{gathered}$

you need to remove what accompanies z in this case we add 9 to both sides to remove the -9