5.

Simplify the expression.

a5 ∙ 3b9 ∙ 6a

18a6b9

10a6b9

18ab15

18a45b9

1 answer

To simplify the given expression \( a^5 \cdot 3b^9 \cdot 6a \):

1. First, rearrange and group the coefficients and like terms:

\[ 3 \cdot 6 \cdot a^5 \cdot a \cdot b^9 \]

2. Multiply the coefficients:
\[ 3 \cdot 6 = 18 \]

3. Combine the a terms using the rule \( a^m \cdot a^n = a^{m+n} \):
\[ a^5 \cdot a = a^{5+1} = a^6 \]

4. The b term remains as is because there is no other \( b \) term to combine:
\[ b^9 \]

So the simplified expression is:

\[ 18a^6b^9 \]

Thus, the correct answer is:
\[ 18a^6b^9 \]