1/9 - (k+3)/(72K) = 1/(9k) - (k-1)/(8k)

Answer 1

1/9 - (k+3)/(72K) = 1/(9k) - (k-1)/(8k)
multiply each term by 72k

8k - (k+3) = 8 - 9(k-1)
8k - k - 3 = 8 - 9k + 9
16k = 20
k = 20/16 = 5/4 or 1.25