Answer:
n=-6
Step-by-step explanation:
Equate the equation to zero
3(n+6)=0
Open the bracket
3n+18=0
Substrate 18 from both sides
3n=-18
Divide both sides by 3
Therefore the answer to that given equation is -6
The quandrants on a grap are basically the groups on the graph like quadrant I ,II ,III , and IV hope that helps