Solve for the unknown 6d - 7 = 1 + 3(d + 6)

6d - 7 = 1 + 3(d + 6)

6d - 7 = 1 + 3(d) (3)( + 6)

6d - 7 = 1+3d+18

6d - 7 = 3d+19

6d - 7 +7= 3d+19+7

6d=3d+26

6d-3d=3d+26-3d

3d=26

3d/3=26/3

d=8.67