12abx² - (9a² - 8b²)x - 6ab = 0

12abx² - 9a² x + 8b²x - 6ab = 0

3ax(4bx - 3a) + 2b(4bx - 3a) = 0 taking 3ax common from first two terms and 2b from last two

(4bx - 3a) (3ax + 2b) = 0

(4bx - 3a) = 0 or (3ax + 2b) = 0

Hence the roots of equation are