To do this let's put 129 where X is, like this: -12(129)+14(129)-6(129)
Now we multiply -12 by 129, which is equal to -1548.
Now we multiply 14 by 129, which is equal to 1806.
Now we multiply -6 by 129, which is equal to -774.
Now, let's put these numbers into an equation, like this: -1548+1806-(-774).
The answer to this equation is 1032.
I hope this helps.
