Answer:
C. [tex]9^{-2} = \frac{1}{81}[/tex]
Step-by-step explanation:
Given
[tex]9^{x}[/tex]
Required
Find the expression where x - 2
[tex]9^{x}[/tex]
Substitute 2 for x
[tex]9^{-2}[/tex]
From law of indices which states
[tex]a^{-b} = \frac{1}{a^b}[/tex]
So, the expression becomes
[tex]9^{-2} = \frac{1}{9^2}[/tex]
Expand the denominator
[tex]9^{-2} = \frac{1}{9 * 9}[/tex]
[tex]9^{-2} = \frac{1}{81}[/tex]
Hence, [tex]9^{x}[/tex] is [tex]\frac{1}{81}[/tex] when x = 2