To solve the inequality:
u + 7 < 18
We need to isolate the variable u on one side of the inequality symbol.
Subtracting 7 from both sides, we get:
u < 18 - 7
Simplifying the right-hand side, we get:
u < 11
Therefore, the solution to the inequality is:
u < 11
In interval notation, the solution is:
(-∞, 11)