Answer: 
<u>Simplify both sides of the equation</u>

<u>Subtract 5n from both sides</u>

<u>Subtract 15 from both sides</u>

No the sum of measures would exceed 180, therefore it would not be a obtuse triangle
5/8 * 4/5
5*4 20 1
----- = ----- = ---
8*5 40 2
5/8 * 4/5 = 1/2 or .5
1. 17
2. 21
3. 25
4. 29
5. 33
Just take the 13, then add 8, then subtract 4, then with what you got keep going on to the next term.