Answer:
A = -129
Step-by-step explanation:
Equation given:
[tex]141+a=12[/tex]
You're looking for a. That means it has to be alone. To leave it alone, you have to subtract 141 from both sides.
[tex]141+a-141 = 12-141[/tex]
[tex]12-141=-129[/tex]
Therefore,your answer will be -129.