Question

ПОМОГИТЕ ПОЖАЛУЙСТА!
Найдите x1 и x2 и все с решением

Answer 1

Ответ:

Пошаговое объяснение:

1.

x² + 7x + 10 = 0

D = 49 - 40 = 9

x₁ = $\frac{-7 + 3}{2}$ = -2

x₂ = $\frac{-7 - 3}{2}$ = -5

2.

x² - x - 20 = 0

D = 1 + 80 = 81

x₁ = $\frac{1 + 9}{2}$ = 5

x₂ = $\frac{1 - 9}{2}$ = -4

3.

x² + 6x - 7 = 0

D = 36 + 28 = 64

x₁ = $\frac{-6 + 8}{2}$ =  1

x₂ = $\frac{-6 - 8}{2}$ = -7

4.

x² + 11x + 24= 0

D = 121 - 96 = 25

x₁ = $\frac{-11 + 5}{2}$ =  -3

x₂ = $\frac{-11 - 5}{2}$ =  -8

5.

x² + 17x + 70 = 0

D = 289 - 280 = 9

x₁ = $\frac{-17 + 3}{2}$ =  -7

x₂ = $\frac{-17 - 3}{2}$ =  -10

6.

x² - 7x - 30 = 0

D = 49 + 120 = 169

x₁ = $\frac{7 + 13}{2}$ =  10

x₂ = $\frac{7 - 13}{2}$ =  -3

7.

x² + 10x - 11 = 0

D = 100 + 44 = 144

x₁ = $\frac{-10 + 12}{2}$ =  1

x₂ = $\frac{-10 - 12}{2}$ =  -11

8.

x² + x - 12 = 0

D = 1 + 48 = 49

x₁ = $\frac{-1 + 7}{2}$ =  3

x₂ = $\frac{-1 - 7}{2}$ =  -4

9.

x² +11x + 28 = 0

D =  121 - 112 = 9

x₁ = $\frac{-11 + 3}{2}$ =  -4

x₂ = $\frac{-11 - 3}{2}$ =  -7

10.

x² - 4x -21 = 0

D = 16 +84 = 100

x₁ = $\frac{4 + 10}{2}$ =  7

x₂ = $\frac{4 - 10}{2}$ =  3

11.

x² + 4x + 3 = 0

D = 16  - 12 = 4

x₁ = $\frac{-4 + 2}{2}$ =  -1

x₂ = $\frac{-4 - 2}{2}$ =  -3

12.

x² + 7x - 18 = 0

D = 49 + 72 = 121

x₁ = $\frac{-7 + 11}{2}$ =  2

x₂ = $\frac{-7 - 11}{2}$ =  -9

13.

x² + 6x + 5 = 0

D = 36 - 20 = 16

x₁ = $\frac{-6 + 4}{2}$ =  -1

x₂ = $\frac{-6 - 4}{2}$ =  -5

14.

x² - 9x + 14 = 0

D = 81 - 56 = 25

x₁ = $\frac{9 + 5}{2}$ =  7

x₂ = $\frac{9 - 5}{2}$ =  2

15.

x² + 13x +42 = 0

D = 169 - 168 = 1

x₁ = $\frac{-13 + 1}{2}$ =  -6

x₂ = $\frac{-13 - 1}{2}$ =  -7

16.

x² + 2x  -3 = 0

D = 4  + 12 = 16

x₁ = $\frac{-2 + 4}{2}$ =  1

x₂ = $\frac{-2 - 4}{2}$ =  -3

17.

x² - x - 12 = 0

D = 1 +48 = 49

x₁ = $\frac{1 + 7}{2}$ =  4

x₂ = $\frac{1 - 7}{2}$ =  3

18.

x² + 12x + 35 = 0

D = 144 - 140 = 4

x₁ = $\frac{-12 + 2}{2}$ = -5

x₂ = $\frac{-12 - 2}{2}$ =  -7

19.

x² - 10x + 21 = 0

D = 100 - 84 = 16

x₁ = $\frac{10 + 4}{2}$ =  7

x₂ = $\frac{10 - 4}{2}$ =  3

20.

x² - x - 30 = 0

D = 1 + 120 = 121

x₁ = $\frac{1 + 11}{2}$ =  6

x₂ = $\frac{1 - 11}{2}$ =  5

21.

x² - 9x + 20 = 0

D = 81 - 80 = 161

x₁ = $\frac{9 + 13}{2}$ =  11

x₂ = $\frac{9 - 13}{2}$ =  -2

22.

x² - 11x + 24 = 0

D = 121 -96 = 25

x₁ = $\frac{11 + 5}{2}$ =  8

x₂ = $\frac{11 - 5}{2}$ =  3