Answer:
[tex]a=12[/tex]
Step-by-step explanation:
Work backwards with synthetic division with remainder 0 and then solve for a:
-3 | 2 a 19 3
_________
2 | 0
-3 | 2 a 19 3
_______ -3
2 | 0
-3 | 2 a 19 3
_______ -3
2 1 | 0
-3 | 2 a 19 3
_____-18 -3
2 1 | 0
-3 | 2 a 19 3
_____ -18 -3
2 6 1 | 0
-3 | 2 a 19 3
_____ -18 -3
2 6 1 | 0
-3 | 2 a 19 3
____-6 -18 -3
2 6 1 | 0
a - 6 = 6
a = 12
