Question 97658
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I need help completing the square for this problem.

16x^2-16x-5=0

So far I have tried this:

16x^2-16x+[1/2(-16)]=5+[1/2(-16)]
16x^2-16x+64=5+64
16(x^2-x+4)=69
16(????????????
 
I'm lost from this point on. I tried factoring but it's not working for me. I hope you can help me.

Thank you very much

Solve a Quadratic Equation by completing the square. 

I was not sure what would be an acceptable answer for your teacher so I worked it all the way out.
This problem is a Quadratic Equation. Here is your solution.
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You would be lost, because you should've FIRST divided through, by 16, in order to make the coefficient on {{{x^2}}}, 1.
{{{16x^2 - 16x - 5 = 0}}}
This quadratic can be solved by FACTORING. Often-times, this author will solve, by FACTORING, if possible, 
before or after completing the square, and then match the solutions. You can do the same, if you wish!

           {{{16x^2 - 16x - 5 = 0}}}
         {{{16x^2/16 - 16x/16 - 5/16 = 0/16}}}----- Dividing each side by 16
                 {{{x^2 - x - 5/16 = 0}}} 
                         {{{x^2 - x = 5/16}}} ----- Adding {{{5/16}}} to both sides
{{{x^2 - x + ((1/2)(- 1))^2 = 5/16 + ((1/2)(- 1))^2}}} ---- Squaring {{{1/2}}} of b, then adding result to both sides
          {{{x^2 - x + (- 1/2)^2 = 5/16 + (- 1/2)^2}}} 
                    {{{(x - 1/2)^2 = 5/16 + 1/4}}} 
                   {{{(x - 1/2)^2 = 5/16 + 4/16}}} 
                  {{{(x - 1/2)^2 = 9/16}}} 
            {{{sqrt((x - 1/2)^2) = 0 +- sqrt(9/16)}}} ---- Taking square root on both sides
                       {{{x - 1/2 = 0 +- 3/4}}} 
                            {{{x = 1/2 +- 3/4}}}
                            {{{x = 2/4 +- 3/4}}} 
                   {{{system(highlight(matrix(2,1, x = 2/4 + 3/4 = 5/4, x = 2/4 - 3/4 = - 1/4)))}}}</font></font></font></b></pre>