(2х - 3y)² - (2x + 5y)² = (2x - 3y - (2x + 5y)) * (2x - 3y + (2x + 5y)) = (2x - 3y - 2x - 5y) * (2x - 3y + 2x + 5y) = (- 8y) * (4x + 2y) = (- 8y) * 2 (2x + y) = - 8 * 2y * (2x + y) = - 16y * (2x + y)
4х -6у+4х-10у
-6у-10у= -16у²
-16у/2
-8у
