To simplify the expression 18 - 2[x + (x - 5)], we use the distributive property of multiplication. In this case, we multiply first the terms enclosed in parentheses. The inner terms are considered first, that is 18 - 2[x + x - 5], then 18 - 2[2x - 5]. We use again the distributive property, 18 - 4x +10 .The final answer is 28 - 4x.