Question

Ayuda urgenteeeeeeeeeeeee​

Answer 1

Respuesta:

te las pongo abajo :)

Explicación paso a paso:

a) 7x² - 6x = 5

7x² - 6x - 5 = 0

a = 7

b= -6

c= -5

{- (-6) +- √ [(-6)² - 4(7)(-5)]} / 2(7)

{- (-6) +- √ [36 + 140]} / 14

{+6) +- √ [176]} / 14

x1 = {+6 + 13.27 } / 14

x1 = { 19.27 } / 14

x1 = 1.38

x2 = {+6 - 13.27 } / 14

x2 = { - 7.27 } / 14

x2 = - 0.52

** comprobación **

7x² - 6x - 5 = 0

7(-0.52)² - 6(-0.52) - 5 = 0

7(0.2704) + 3.12 -5 = 0

1.8928 + 3.12 - 5 = 0

5.01 - 5 ≈ 0

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b ) (-3/5 x²) = 2

(-3x²) = 2(5)

(-3x²) = 10

x² = 10/-3

x² = (-3.34)

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c) x² - x (3x - 1) = 0

x² - 3x² + x = 0

- 2x² + x = 0

x (-2x + 1) = 0 (x)

(- 2x + 1) = 0

-2x = -1

x = -1 / -2

x = 1/2

** comprobación **

- 2x² + x = 0

- 2(1/2)² + (1/2) = 0

- 2(0.50)² + (0.50) = 0

-2(0.25)+(0.50) = 0

-0.50 + 0.50 =0

0 = 0

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d) -x² + 7x = x(4x - 3)

-x² + 7x = 4x² - 3x

-x² + 7x - 4x² + 3x = 0

- 5x² + 10x = 0

(5x) (-x + 2) = (5x) 0

-x + 2 = 0

-x = -2

x = 2

** comprobación **

-x² + 7x - 4x² + 3x = 0

-(2)² + 7(2) - 4(2)² + 3(2) = 0

- 4 + 14 - 4(4) + 6 = 0

- 4 + 14 - 16 + 6 = 0

0 = 0

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e) 6x (7 + x) = (x + 5)²

42x + 6x² = x² + 2(x)(5) + (5)²

42x + 6x² = x² + 10x + 25

42x + 6x² - x² - 10x - 25 = 0

32x + 5x² - 25 = 0

5x² + 32 x - 25 = 0

a = 5

b= 32

c= -25

{- (32) +- √ [(32)² - 4(5)(-25)]} / 2(5)

{- 32 +- √ [1024 - 500]} / 10

{- 32 +- √ [524]} / 10

{- 32 +- 22.89} / 10

x1 = {-32 + 22.89 } / 10

x1 = { -9.11 } / 10

x1 = -0.911

x2 = {-32 - 22.89 } / 10

x2 = { - 54.89 } / 10

x2 = - 5.49

** comprobación **

5x² + 32 x - 25 = 0

5 (-5.49)² + 32 (-5.49) - 25 = 0

5 (30.14) + 32 (-5.49) - 25 = 0

150.70 - 175.68 - 25 = 0

24.98 - 25 ≈ 0

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f) (3x-1) (-2x+2) = (2x-1) (2x+3)

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

-6x² + 6x + 2x - 2 = 4x² + 6x - 2x - 3

-6x² + 6x + 2x - 2 - 4x² - 6x + 2x + 3 = 0

-10x² + 4x + 1 = 0

10x² - 4x - 1 = 0

a = 10

b= -4

c= -1

{- (-4) +- √ [(-4)² - 4(10)(-1)]} / 2(10)

{ 4 +- √ [16 + 40]} / 20

{ 4 +- √ 56} / 20

{ 4 +- 7.48} / 20

x1 = {4 + 7.48 } / 20

x1 = { 11.48 } / 20

x1 = 0.574

x2 = {4 - 7.48 } / 20

x2 = { - 3.48 } / 20

x2 = - 0.174

** comprobación **

10x² - 4x - 1 = 0

10(0.574)² - 4(0.574) - 1 = 0

10(0.33) - 2.296 - 1 = 0

3.30 - 2.296 - 1 = 0

1.004 ≈ 0