5.
Possible rational solutions are ±1, ±2, ±3, ±5, ±6, ±10, ±15, ±30
Try 2
1 | 1  -1 -19  49 -30
  |     1   0 -19  30
    1   0 -19  30   0
So we have factored P(x) as 
Possible rational solutions to the second parenthetical expression
set = 0 are ±1, ±2, ±3, ±5, ±6, ±10, ±15, ±30
Try 2
2 | 1   0 -19  30
  |  2   4 -30
    1   2 -15   0
So we have factored P(x) further as as
Now just factor the trinomial:
x-1=0;  x-2=0;  x+5=0;  x-3=0
  x=1;    x=2     x=-5    x=3
Edwin