-9 / (2k) + (2/9) = -3 - 2 / (3k)

9 / (2k) - (2/9) = 3 + 2 / (3k)

(9 * 9 - 2 * 2k) / (9 * 2k) = (3 * 3k + 2) / (3k)

(81 - 4k) / (18k) = (9k + 2) / (3k)

3k * (81 - 4k) = 18k * (9k + 2)

81 - 4k = 6 * (9k + 2)

81 - 4k = 54k + 12

81 - 12 = 54k + 4k

69 = 58k

69 / 58 = k