It simple asks you to multiple 9 by 12.
Z is a variable / a setting unknown number is divided by 12 to give you 9
To find
Z you would have to take the ÷12 to the opposite side crossing over the = sign
which will make it the ÷ sign to change it the opposite which is × ( the opposite of ÷ is × and the opposite of - is + )
You are now left with
Z = 9 × 12
and you know that 9 × 12 is 108 which makes Z, 108.
Z = 108
