Question

what's the missing variable for 1/3n+3=-n-2

Answer 1

$\frac{1}{3}$n + 3 = -n - 2   Multiply both sides by 3 to cancel out the fraction
  n + 9 = -3n - 6   Add 3n to both sides
4n + 9 = 6   Subtract 9 from both sides
      4n = -3   Divide both sides by 4
        n = $- \frac{3}{4}$