Answer:
13
Explanation:
You can think of the 2x + 5 as a rule that works on your input and spits out something new. The rule says to "times by 2 and then add 5" SO... take the input, 4, in this case, 4 × 2 is 8 and then add 5 and out comes the output 13.
in mathey writing it looks like this:
2x+ 5, x = 4
2(4) + 5
8 + 5
13