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Find x:Find x: (3x+7)(x-1) = 24.  

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raydusol | Student, Grade 9 | (Level 2) Honors

Posted May 3, 2011 at 5:55 AM via web

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Find x:

Find x: (3x+7)(x-1) = 24.

 

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giorgiana1976 | College Teacher | (Level 3) Valedictorian

Posted May 3, 2011 at 11:19 AM (Answer #2)

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3x^2 - 3x + 7x - 7 = 24

We'll combine like terms:

3x^2 + 4x - 31 = 0

We'll apply quadratic formula:

x1 = [-4+sqrt(16+372)]/6

x1 = (-2+sqrt97)/3

x2 = (-2-sqrt97)/3

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted May 3, 2011 at 11:36 AM (Answer #3)

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The equation to be solved is : (3x+7)(x-1) = 24

(3x+7)(x-1) = 24

=> 3x^2 + 4x - 7 = 24

=> 3x^2 + 4x - 31 = 0

x1 = -4/6 + sqrt (16 + 372) /6

=> -2/3 + (sqrt 97)/6

x2 = -2/3 - (sqrt 97)/6

The roots of the equation are -2/3 + (sqrt 97)/6 and -2/3 - (sqrt 97)/6

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Wiggin42 | Student, Grade 11 | (Level 2) Valedictorian

Posted April 25, 2014 at 11:57 PM (Answer #5)

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(3x + 7)(x - 1) = 24

3x^2 - 3x +7x - 7 = 24

3x^2 +4x -31 = 0

From this point you can apply the quadratic formula and get two x values. Depending on the situation, one of them might be extraneous. 

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