Answer:
f(6) = 137
Step-by-step explanation:
Plug in 6 for the x value.
f(6) = 21(6) + 11
f(6) = 126 +11
[tex]f(6) = 21(6) + 11 \\ =12 6 + 11 \\ =1 37[/tex]
I hope I helped you^_^