-3n<7n-20<3n
We can split this into two parts
-3n < 7n - 20 7n - 20 < 3n
subtract 7n from both sides
-10n < - 20 -20 < - 4n
divide both sides by -10 divide both sides by -4
Becuse we are dividing both sides by a negative, reverse the inequality signs
n > 2 5 > n
n > 2 and n < 5
So....the solution is
2 < n < 5
So....the sum of the integers that satisfy this is
3 + 4 =
7