Помогите пж голова болит, спать хочу

2)

x ≥ 3    x = 3

x > 13   x = 14

x ≥ - 5  x = -5

x > -7   x = -6

3)

8a + 5b ≥ 3a + 25b

8a - 3a ≥ 25b - 5b

5a ≥ 20b  |:5

a ≥ 4b

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5a - 21b > 12a - 49b

49b - 21b > 12a - 5a

28b > 7a

4b > a

a < 4b

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(x + 4)(x + 6) ≤ x(x + 7)

x² + 4x + 6x + 24 ≤ x² + 7x

4x + 6x - 7x ≤ -24

3x ≤ -24

x ≤ -8

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(x - 9)(x - 2) < (x + 8)(x - 6)

x² - 9x - 2x + 18 < x² - 6x + 8x - 48

-11x + 18 < 2x - 48

13x > 66

x > 66/13 = 5 1/13