The sum of 12abx, 2a2bx, 8abx and 8a2bx is
20abx + 10a2bx
10abx + 20a2bx
30a3b2x2
none of the above
Sum of 12abx, 2a2bx, 8abx and 8a2bx = 12abx + 2a2bx + 8abx + 8a2bx
= (12abx + 8abx) + (2a2bx + 8a2bx)
= 20abx + 10a2bx
This cannot be simplified further as abx and a2bx are unlike terms.
The coefficient of y2 in -10abxy2 is _________.