1) (2x + 1) × (x - 3) - (1 - 3) × (x - 5) = 29 - 11x
2x² - 6x + x - 3 - (x - 5 - x² + 5x) = 29 - 11x
2x² - 6x + x - 3 - (6x - t - x²) = 29 - 11x
2x² - 6x + x - 3 - 6x + 5 + x² = 29 - 11x
3x² - 11x + 2 = 29 - 11x
3x² + 2 = 29
3x² = 29 - 2
3x² = 27
x² = 9
x = ± 3
x¹ = 3
x² = - 3
2) (3x - 8)² - (4x - 6)² + (5x - 3) × (5x + 3) = 96
9x² - 48x + 64 - (16x² - 48x + 36) + 25x² - 4 = 96
9x² - 48x + 64 - 16x² + 48x - 36 + 25x² - 4 = 96
18x² + 24 = 96
18x² = 96 - 24
18x² = 72
x² = 4
x = ± 2
x¹ = 2
x² = - 2
3) (x - 2) × (x² + 2x + 4) - x² × (x - 18) = 0
x³ - 8 - x³ + 18x² = 0
- 8 + 18x² = 0
18x² = 8
x² = 4/9
x = ± 2/3
x¹ = 2/3
x² = - 2/3
так как С стоит перед D, то С вычитается из D (D-C) = (500-100) = 400
1000+(500-100) = 1400