5x + 24 - x² = 0
-x² + 5x + 24 = 0
x² - 5x - 24 = 0
D = (-5)² - 4 * 1 * (-24) = 25 + 96 = 121
x₁ = (5 + √121) / 2 = (5 + 11) / 2 = 16 / 2 = 8
x₂ = (5 - √121) / 2 = (5 - 11) / 2 = -6 / 2 = -3
-(x - 8)(x + 3)
10y² - 13y - 3 = 0
D = (-13)² - 4 * 10 * (-3) = 169 + 120 = 289
y₁ = (13 + √289) / (2 * 10) = (13 + 17) / 20 = 30 / 20 = 3 / 2 = 1.5
y₂ = (13 - √289) / (2 * 10) = (13 - 17) / 20 = -4 / 20 = -1 / 5 = -0.2
10(y - 1.5)(y + 0.2)
y² + 5y + 4 = 0
D = 5² - 4 * 1 * 4 = 25 - 16 = 9
y₁ = (-5 + √9) / 2 = (-5 + 3) / 2 = -2 / 2 = -1
y₂ = (-5 - √9) / 2 = (-5 - 3) / 2 = -8 / 2 = -4
(y + 1)(y + 4)
3x² - 3x - 90 = 0
x² - x - 30 = 0
D = (-1)² - 4 * 1 * (-30) = 1 + 120 = 121
x₁ = (1 + √121) / 2 = (1 + 11) / 2 = 12 / 2 = 6
x₂ = (1 - √121) / 2 = (1 - 11) / 2 = -10 / 2 = -5
3(x - 6)(x + 5)
2x² - 3x - 90 = 0
D = (-3)² - 4 * 2 * (-90) = 9 + 720 = 729
x₁ = (3 + √729) / (2 * 2) = (3 + 27) / 4 = 30 / 4 = 15 / 2 = 7.5
x₂ = (3 - √729) / (2 * 2) = (3 - 27) / 4 = -24 / 4 = -6
2(x - 7.5)(x + 6)
x² - 6x + 9 = (x - 3)²
Здесь использована формула сокращенного умножения: квадрат разности (a - b)² = a² - 2ab + b².
-x² + x - 12
D = 1 - 4*(-1)*(-12) = 1 - 48 = -47
Т.к. дискриминант меньше нуля, то разложить на множители нельзя.
x² - 14x + 45 = 0
D = (-14)² - 4 * 1 * 45 = 196 - 180 = 16
x₁ = (14 + √16) / 2 = (14 + 4) / 2 = 18 / 2 = 9
x₂ = (14 - √16) / 2 = (14 - 4) / 2 = 10 / 2 = 5
(x - 9)(x - 5)
(x - 1)(x + 4)
Тут уже разложено на множители.
x² - 5x + 6 = 0
D = (-5)² - 4 * 1 * 6 = 25 - 24 = 1
x₁ = (5 + √1) / 2 = (5 + 1) / 2 = 6 / 2 = 3
x₂ = (5 - √1) / 2 = (5 - 1) / 2 = 4 / 2 = 2
(x - 3)(x - 2)
x² + 5x - 6 = 0
D = 5² - 4 * 1 * (-6) = 25 + 24 = 49
x₁ = (-5 + √49) / 2 = (-5 + 7) / 2 = 2 / 2 = 1
x₂ = (-5 - √49) / 2 = (-5 - 7) / 2 = -12 / 2 = -6
(x - 1)(x + 6)
3x² - 14x + 16 = 0
D = (-14)² - 4 * 3 * 16 = 196 - 192 = 4
x₁ = (14 + √4) / (2 * 3) = (14 + 2) / 6 = 16 / 6 = 8 / 3
x₂ = (14 - √4) / (2 * 3) = (14 - 2) / 6 = 12 / 6 = 2
3(x - 8/3)(x - 2)
5x² - 6x + 1 = 0
D = (-6)² - 4 * 5 * 1 = 36 - 20 = 16
x₁ = (6 + √16) / (2 * 5) = (6 + 4) / 10 = 10 / 10 = 1
x₂ = (6 - √16) / (2 * 5) = (6 - 4) / 10 = 2 / 10 = 1 / 5
5(x - 1)(x - 1/5)
x² - 8x + 16 = 0
D = (-8)² - 4 * 1 * 16 = 64 - 64 = 0
x = 8 / 2 = 4
(x - 4)²
Ответ: [указаны выше для каждого примера]