I need help on this please some one can help me solve this p4

Answer:
d = 10
Step-by-step explanation:
3/4(6 + d) = 12
(18 + 3d)/4 = 12
18 + 3d = 48
3d = 48 - 18
3d = 30
d = 30 : 3
d = 10
multiple both sides by 4/3
move the constant to the right
subtract the numbers