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Chapter 4 : Algebra
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Author:  admin [ Fri Mar 28, 2014 3:28 pm ]
Post subject:  Chapter 4 : Algebra

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Author:  jfu.green [ Sun Aug 18, 2019 5:17 pm ]
Post subject:  Re: Chapter 4 : Algebra

Can someone please explain to me how was one able to come to the conclusion that B is the correct answer?

Also, how did they get 12y and 109?

Thanks!

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Author:  sr_vineeth_ruveneco [ Mon Aug 26, 2019 10:18 pm ]
Post subject:  Re: Chapter 4 : Algebra

Hi jfu.green,

Here is a step-by-step process in solving the equation:

y = 3x^2 - 5x - 7 Step 1: multiply both sides by 12
12y = 36x^2 - 60x - 84 Step 2: add 109 to both sides so that the term on the right can be factored
12y + 109 = 36x^2 -60x +25 Step 3: Factor the right side
12y + 109 = (6x - 5)^2 Step 4: square root both sides
sqrt (12y + 109) = 6x - 5 Step 5: add 5 to both sides
5 + sqrt (12y + 109) = 6x Step 6: divide both sides by 6
5 + sqrt (12y + 109) / 6 = x

Hope this helps!
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