To rewrite the expression $6^4 \times 6^5$ as a base to a power, you can use the product of powers property. This property states that:

$a^m \times a^n = a^{m+n}$

Here, the base $a$ is $6$, and the exponents are $4$ and $5$. Applying the rule:

$6^4 \times 6^5 = 6^{4+5} = 6^9$

Thus, $6^4 \times 6^5 = 6^9$.

Would you like more details on exponent rules, or do you have any other questions?

Here are 5 related questions:

1. How would you simplify $2^3 \times 2^7$?
2. What is $(3^2)^3$ using the power of a power rule?
3. How do you simplify $5^6 / 5^2$?
4. Can you rewrite $7^0 \times 7^5$ as a single exponent?
5. What is the result of $10^4 \times 10^0$?

Tip: When multiplying numbers with the same base, always add the exponents!