Given:
To determine the value of "x", we can isolate it in the equation (x + 3 = 18). This can be done by subtracting 3 to both sides of the equation.
⇒ x + 3 - 3 = 18 - 3
⇒ x = 15
To verify that the value of "x" is 15, we need to substitute the value of x into the inequality (x > 10).
⇒ x < 10
⇒ 15 < 10 (True)
Therefore, the value of "x" is 15.