42=-2d+6 move the constant to the other side (subtract)
36=-2d since -2d is multiplying divide it
-18=d switch sides
d=-18 you're done!
Hope this helps, now you know the answer and how to do it. HAVE A BLESSED AND WONDERFUL DAY! As well as a great rest of Black History Month! :-)
- Cutiepatutie ☺❀❤