Answer:
[tex]f(-3)=343[/tex]
Step-by-step explanation:
[tex]f(x)=(\frac{1}{7} )^x[/tex]
Plug -3 into x and solve using the negative power rule:
[tex]x^{-a}=\frac{1}{x^a}[/tex]
[tex]f(-3)=(\frac{1}{7} )^{-3} \\\\f(-3)=\frac{1}{\frac{1}{7}^3 } \\\\f(-3)=\frac{1}{\frac{1}{343} } \\\\f(-3)=343[/tex]
Sorry, those fractions got very small. Let me know if I need to clarify anything there