With some simple rearrangement, we can rewrite the numerator as

Then factorizing the difference of squares,
, we end up with

Answer:
B: $12.00 per backpack gives the maximum revenue; the maximum revenue is $312.00.
Step-by-step explanation:
Answer:
I think the answer is 70
Step-by-step explanation:
40 + 15 = 55 and when you add 15 to 55 you get 70 but this might not be right!