Answer: d = 147/4 or 36.75
Edward didn't isolate for 'd' by rearranging the terms.
(4/7)d = 21 (Multiply both sides by 7 to get rid of the 7 on the left side)
4d = 21 · 7
4d = 147 (Divide both sides by 4 to isolate for d)
d = 147/4 or 36.75
5.9m questions
7.7m answers