2 - 3d = 4d - 19
Add the opposite to both sides to get the variable on the left side only.
2 - 3d = 4d - 19
-4d -4d
2 - 7d = - 19
Then get the terms w/o variables on the right,
2 - 7d = - 19
-2 -2
-7d = -21
Then divide by the number paired with the variable.
--7d = -21
----- ----- ; d = 3
-7 -7
Final answer = 3
Hope I helped :)
