m=18 kg

w=?
solve

That's as far as you can go with that equation. You might be a smart alec and say that a "w" is an upside down "m," so "w" equals 81...but your math teacher wouldn't agree. :)

w=mg

w=(18)(9.8)

=176.4 N..

hahaha..it's called PHYSICS~

To solve for the value of "w," we need some additional information or context. Please provide more details about the equation or problem you are trying to solve.