Answer:
f(3) = 10
Step-by-step explanation:
If x = 3 then fill in the x's on the original equation and solve;
f(x) = 2x + 4
f(3) = 2(3) + 4
2 x 3 = 6
6 + 4 = 10
So, f(3) = 10
Hope this helps!!!