These are step-by-step instruction for this question:
f(x)=7x-3 First, you write down the answer
f(3)=7(3)-3 Secondly, you need to substitute the x with 3
f(3)=21-3 Next, Multiply 7 to 3 which is 21
f(3)=18 Then, Subtract 21 to 3 which is 18
Answer: So f(3) is 18
