what is the value of n if the lines are parallel? perpendicular?

I assume these numbers represent the slopes of the two lines.

 

If the lines are parallel then the slopes are the same, so

n/9 = 3/2

Multiply both sides by 9 to get n = 27/2

 

If the lines are perpendicular then when the slopes are multiplied together the result is -1, so

(n/9)*(3/2) = -1

n/6 = -1

n = -6