SOLUTION: In the process of completing the square, 3x²+7x=12 becomes x^2+7/4x=4 True or False

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Question 608704: In the process of completing the square, 3x²+7x=12 becomes x^2+7/4x=4
True or False

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
3x² + 7x = 12
So you asked if that becomes:  x² + 7%2F4x = 4?
No because the first step is to divide through by the
coefficient of x², which is 3. And we divide all the terms,
on both sides by 3 

3%2F3x² + 7%2F3x = 12%2F3

           x² + 7%2F3x = 4 

 So 7%2F4 has the wrong enominator.

But it seems a shame to stop here and not go on and
complete the square.  Let's do it just for fun:
(You can print it for future use, because you're
going to have to learn how to do that soon.
 

multiply 1%2F2 times 7%2F3, get 7%2F6
Square 7%2F6. get 49%2F36

Add that to BOTH sides of the equation, to keep
it balanced.
  
So now we have:

x² + 7%2F3x+49%2F36 = 4+49%2F36

That factors as:

(x + 7%2F6)² = 193%2F36

Now we use the principle of square roots:

 x + 7%2F6 = %22%22+%2B-+sqrt%28193%2F36%29
 
 x + 7%2F6 = %22%22+%2B-+sqrt%28193%29%2F6%29

             x = -7%2F6+%2B-+sqrt%28193%29%2F6%29

             x = %28-7+%2B-+sqrt%28193%29%29%2F6

Edwin