How do u figure out the problem of 1/5d = - 3

So 1/5d=-3 so you multiply both sides by 5d/1 so you get

5d/1 times 1/5d=5d/1 times - 3/1

so the above statement simplifies to 5d/5d=5d times - 3 or

1=-15d

so you multiply both sides by - 1

-1=15d

divide both sides by 15

-1/15=d