(c + 24d)² - (24c + d)² = (c + 24d + 24c + d)(c + 24d - 24c - d) =
= (25c + 25d)(23d - 23c)= 25 * 23 * (c + d)(d - c) = 575(c + d)(d - c)
(c + 24d)² - (24c + d)² = (c + 24d + 24c + d)(c + 24d - 24c - d) =
= (25c + 25d)(23d - 23c)= 25 * 23 * (c + d)(d - c) = 575(c + d)(d - c)