Answer: Lower-right corner [tex]3^7 \times \frac{1}{3^4}[/tex]
Explanation:
We use the rule that
[tex]a^{-b} = \frac{1}{a^b}[/tex]
The negative exponent tells us to apply the reciprocal if we want the exponent to be positive.
In this case, a = 3 and b = 4
So,
[tex]a^{-b} = \frac{1}{a^b}\\\\3^{-4} = \frac{1}{3^4}[/tex]
which is why overall,
[tex]3^7\times 3^{-4} = 3^7 \times \frac{1}{3^4}[/tex]