Add: (4d − 3)+(12d + 4) .

To add the two expressions, we simply combine the like terms.

(4d - 3) + (12d + 4)

= 4d + 12d - 3 + 4

= (4d + 12d) + (-3 + 4)

= 16d + 1

So, the sum of (4d - 3) and (12d + 4) is 16d + 1.