a) (-9a + 4b)² = 81a² - 72ab + 16b².
б) (-11x - 7y)² = 121x² + 154xy + 49y².
в) (-0.8x - 0.5b)² = 0.64x² + 0.8xb + 0.25b².
г) (-1/3 p + 6q)² = 1/9 p² - 4pq + 36q².
д) (0.08a - 50b)² = 0.0064a² - 8ab + 2500b².
е) (-0.5x - 60y)² = 0.25x² + 60xy + 3600y².