Question

How do you solve `L = a + (n - L)d` for d?

Answer 1

`d=(L-a)/(n-L)`

Explanation:

Subtract `a` from both sides.

`L-a=(n-L)d`

Divide both sides by `(n-L)`

`(L-a)/(n-L)=d`

Rewrite

`d=(L-a)/(n-L)`