The best way I can explain the elimination method is, it's a method where you either add or subtract equations in order to get rid of a variable.
Answer: 
Step-by-step explanation:
Given
New mail carrier takes 4 hours for delivery i.e.
New mail carrier completes
part of work in 1 hour
Old mail carrier takes 3 hours for delivery i.e.
mail carrier completes
part of work in 1 hour
If they work together, they complete the work in x hours i.e.

Answer:
7 miles
Step-by-step explanation:
Mr. Luna's travels east and west are irrelevant to the question. He drives 3 miles north, then he drives 4 more miles north. 3 + 4 = 7, so Mr. Luna ends up 7 miles north of his home.
2/3, since those numbers can be divided by 14.