Ayuda a resolver las ecuaciones cuadraticasa) 21x² + 100 = - 5b) 2x² - 6x = 6x² - 8xc) (x - 3) - (2x + 5)² = - 16d) (4x - 1) (2x + 3) = (x + 3) (x - 1)?

A) 21x² + 100 = - 5 ; 21X² + 105 ═ 0 ; Donde a = 21 ; b = 0 ; c = 105

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X1 = + [93.

9148 i] / 42 = 2.

236 i

X2 = - [93.

9148 i] / 42 = - 2.

236 i

b) 2x² - 6x = 6x² - 8x ; 0 = 6X² - 2X² - 8X + 6X ; 0 = 4X² - 2X

Donde a = 4 ; b = - 2 ; c = 0

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X1 = [2 + 2] / 8 = 1 / 2

X2 = [2 - 2] / 8 = 0

c) (x - 3) - (2x + 5)² = - 16 ; (X - 3) - (4X² + 20X + 25) = 16

X - 3 - 4X² - 20X - 25 = - 16 - 4X² - 19X - 28 = - 16

0 = 4X² + 19X + 12

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X1 = [ - 19 + 13 ] / 8 = - 3 / 4

X2 = [ - 19 - 13] / 8 = - 4

d) (4x - 1) (2x + 3) = (x + 3) (x - 1)

(4x - 1) (2x + 3) = 8X² + 12X - 2X - 3 ; = 8X² + 10X - 3

(x + 3) (x - 1) = X² - X + 3X - 3 ; X² + 2X - 3 8X² + 10X - 3 = X² + 2X - 3

7X² + 8X = 0 ; Donde a = 7 ; b = 8, C = 0

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X1 = [ - 8 + 8] / 14 = 0

X2 = [ - 8 - 8] / 14 = - 16 / 14 = - 8 / 7.