ac² - ad + c³ - cd - bc² + bd
c(ac - d) + c²(c - b) - d(ac - d)
(c + c²)(ac - d) - b(c - c²)(c - d)
(c + c²)(ac - d) - b(c - c)(c + d)
(c + c² - b)(ac - d)
ac² - ad + c³ - cd - bc² + bd
c(ac - d) + c²(c - b) - d(ac - d)
(c + c²)(ac - d) - b(c - c²)(c - d)
(c + c²)(ac - d) - b(c - c)(c + d)
(c + c² - b)(ac - d)