Answer:
6^18.
Step-by-step explanation:
To rewrite (6^9)^2 using a single exponent, we can use the exponent property that states (a^b)^c = a^(b*c).
First, let's simplify the expression inside the parentheses: (6^9)^2.
To do this, we multiply the exponents together: 9 * 2 = 18.
Now, we can rewrite the expression as 6^(9*2) or 6^18.
Therefore, (6^9)^2 is equivalent to 6^18.