To determine the constant term in the expression [tex]\(15x^2 + 2x + 9\)[/tex], we need to identify which part of the expression does not depend on the variable [tex]\(x\)[/tex].
Here is a step-by-step analysis of each term in the expression:
1. [tex]\(15x^2\)[/tex]: This term includes the variable [tex]\(x\)[/tex], specifically [tex]\(x\)[/tex] raised to the power of 2. Thus, this term will change with different values of [tex]\(x\)[/tex].
2. [tex]\(2x\)[/tex]: This term also includes the variable [tex]\(x\)[/tex]. Since it changes with different values of [tex]\(x\)[/tex], it is not a constant term.
3. 9: This term does not include the variable [tex]\(x\)[/tex]. It is a standalone number that does not change regardless of the value of [tex]\(x\)[/tex].
Since the constant term is the one that remains unchanged irrespective of the value of [tex]\(x\)[/tex], we conclude that the constant term in the expression [tex]\(15x^2 + 2x + 9\)[/tex] is:
\[
\boxed{9}
