Answer :
To get the answer we have to substitute x=3 and add 6 to the result.
Lets do this
f(x)=7-2x
f(3)=7-2*3=7-6=1
f(3)+6=1+6=7 - its the result
Lets do this
f(x)=7-2x
f(3)=7-2*3=7-6=1
f(3)+6=1+6=7 - its the result
