Question 651637
Solving for the function, you just need to substitute x as the given f(value)

f(x)=7x+1
So f(3) will be
f(3)=7(3)+1   -Just substitute
f(3)=21+1
f(3)=24

f(x)=7x+1
So f(5) will be
f(5)=7(5)+1   -Just substitute
f(5)=35+1
f(5)=36

f(x)=7x+1
So f(0) will be
f(0)=7(0)+1   -Just substitute
f(0)=0+1
f(0)=1