Respuesta :

3d+9
If you are solving for d then d=-3.
Hope this is helpful! :D
7d + 12 - 4d - 3
3d +9
(- signs attach to the number that comes after them, making that number a negative)
you combine 7d and -4d to give you 3d
you combine 12 and -3 to give you 9
giving you the answer of 3d+9