I NEED HELP PLEASEEE calculate the steepness (angle from base to the top) of each ski run (Bobsled Bop, Dare Devil Drop, Avalanche Alley, Thunder Run) using the cosine ratio and inverse ratio

The first side of a triangle measures 5 in less than the second side, the third side is 3 in more than the first side, and the perimeter is 17 in. how long is the third side? if s represents the length of the second side, which of the following represents the length of the third side? s-5 ws-2 s+ 3 next question ask for turn it in