Answer:
7
Step-by-step explanation:
By using the formula you just need to place -3 where X is being that X will represent F. After placing -3 where it needs to be it should look like this:
4-(-3)
Remove the parathesis and whenever there is a - in front of - in a parathesis you need to change the sign:
4+3
Add the numbers and you get:
7
