The product of 4 and the sum of 7 and a number.
Meaning:
4 ( 7 + n )
The first and only stop of the flight can be Boise, Omaha or Chicago. This means there are 3 possibilities where to stop. From thee the flight connects to New York City, either to La Guardia or to JFK Airport.
1 possible route: Seattle-Boise-La Guardia
<span>2 possible route: Seattle-Omaha-La Guardia
</span><span>3 possible route: Seattle-Chicago-La Guardia
</span><span>4 possible route: Seattle-Boise-NYC
</span><span>5 possible route: Seattle-Omaha-NYC
</span><span>6 possible route: Seattle-Chicago-NYC
</span>
Or in other words: There are two airports where the flight can arrive and for each of them there are three possible routes. So, in total there are 2*3=6 possible routes.
31=2y-5
Add 5 on both -5+5 which cancels out and 31+5 which is 36 and then divide 36 by 2 which equals to 18.
So y=18 hope this helped (':