Question

Answer 1

16x(x - 7)+ (x - 7) = 0

(x - 7)(16x + 1) = 0

x - 7 = 0 hoặc 16x + 1 = 0

*) x - 7 = 0

x = 7

*) 16x + 1 = 0

16x = -1

x = -1/16

Vậy x = -1/16; x = 7

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(3x - 2)² - (2x + 2)² = 0

(3x - 2 - 2x - 2)(3x - 2 + 2x + 2) = 0

(x - 4).5x = 0

x - 4 = 0 hoặc 5x = 0

*) x - 4 = 0

x = 4

*) 5x = 0

x = 0

Vậy x = 0; x = 4

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x² = 5x + 14

x² - 5x - 14 = 0

x² + 2x - 7x - 14 = 0

(x² + 2x) - (7x + 14) = 0

x(x + 1) - 7(x + 1) = 0

(x + 1)(x - 7) = 0

x + 1 = 0 hoặc x - 7 = 0

*) x + 1 = 0

x = -1

*) x - 7 = 0

x = 7

Vậy x = -1; x = 7