Answer:
21
Step-by-step explanation:
1. plug in 4 for F(x) making 4=x:
[tex]f(4)=4(4)+5[/tex]
2. multiply 4 and 4:
[tex]f(4)=4(4) +5[/tex]⇒[tex]f(4)=16+5[/tex]
3. Add 16 and 5 to get your answer:
[tex]f(4)= 16+5[/tex]⇒[tex]f(4)=21[/tex]
