Answer:
1: P = -3
2: X = -60
3: N = 5
Explanation:
Ok, for number one you are going to add 4 on the -4 canceling that out, and adding 4 on the -7 making that -3.
Number 2 you times 10 on the x/10 to cancel out the 10 (making it x) then you do -6 times 10, and then you get -60
Last one is a little tricky here's the equations I used to get the last one
-3 x 8n = -24x
New equation: 4-24x=-104
 +4 + 4
___________________________
 -24x = -100
 ___ ___
 -24 -24
 _
so the answer would be x = 5