To find the value of \(a\) in the equation \((x + 2)^2 = a\) when \(x = 1\), we will follow these steps:
1. Substitute \(x = 1\) into the equation:
[tex]\[
(1 + 2)^2 = a
\][/tex]
2. Simplify the expression inside the parentheses:
[tex]\[
1 + 2 = 3
\][/tex]
3. Square the result:
[tex]\[
3^2 = 9
\][/tex]
So, the value of \(a\) is \(9\).
Therefore, the correct answer is [tex]\(\boxed{9}\)[/tex].
