F(-5) just means that your substituting the number -5 for every x value. So if you have x+1 this would be -5+1 which is -4
Answer:
6
Step-by-step explanation:
add 11 to both sides, that cancels out so then your left with 7x=42, divide by 7 on both sides then you should get x=6
Try looking it up becaus hard to understand
