To determine the value that goes in the empty cell for the function [tex]\( f(x) = 5x \)[/tex] when [tex]\( x = -1 \)[/tex], follow these steps:
1. Notice that the function provided is [tex]\( f(x) = 5x \)[/tex]. This means that for any given value of [tex]\( x \)[/tex], the function [tex]\( f(x) \)[/tex] is calculated by multiplying [tex]\( x \)[/tex] by 5.
2. To find the value of [tex]\( f(x) \)[/tex] when [tex]\( x = -1 \)[/tex]:
[tex]\[
f(-1) = 5 \times (-1)
\][/tex]
3. Perform the multiplication:
[tex]\[
f(-1) = -5
\][/tex]
Thus, the value that belongs in the empty cell for [tex]\( f(x) \)[/tex] when [tex]\( x = -1 \)[/tex] is [tex]\(-5\)[/tex].
The correct answer is [tex]\(-5\)[/tex].
[tex]\[
\boxed{-5}
\][/tex]