Question

What is the value of x when f(x) = 9?

Answer 1

A. 2

EXPLANATION :

From the problem, we have the function :

`f(x)=3^x`

when f(x) = 9 :

`\begin{gathered} f(x)=3^(^x) \\ 9=3^x \end{gathered}`

Note that 9 is 3^2

`\begin{gathered} 9=3^x \\ 3^2=3^x \\ \text{ Since the bases are equal, the exponents are equal too.} \\ 2=x \\ x=2 \end{gathered}`