The answer is p = 5.
Here are the steps I did.
1. Simplify 8p + 10p - p - 8p + 5 to 9p + 5 ( 9p + 5 = 50)
2. Subtract 5 from both sides ( 9p = 50 - 5)
3. Simplify 50 - 5 to 45 ( 9p = 45)
4. Divide both sides by 9 ( 45/9)
5. Simplify 45/9 to 5 ( p = 5)
