SOLUTION: Could someone please help me with this equation??? Solve the quadratic equation bt completing the square. {{{x^2-6x-3=0}}}

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Question 100447: Could someone please help me with this equation??? Solve the quadratic equation bt completing the square.
x%5E2-6x-3=0

Answer by doukungfoo(195) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by completing the square
x%5E2-6x-3=0
First move the term without a variable to the other side of the equal sign
In this problem we'll move the 3
x%5E2-6x=3
Next divide all terms by the number with x%5E2
In this problem there is a 1 so essential we can skip this step.
But I will show the work just to be clear.
x%5E2-6x=3
%28x%5E2%29%2F1-%286x%29%2F1=3%2F1
x%5E2-6x=3
Now take half of the number with x and square it
The number with x in this problem is -6
Half of -6 is -3
-3 squared is 9
Now add 9 to both sides of the equal sign
x%5E2-6x%2B9=3%2B9
x%5E2-6x%2B9=12
Next factor the left hand side to convert it to its squared form
The left side of the equation is x%5E2-6x%2B9
this is converts to %28x-3%29%5E2 because
%28x-3%29%28x-3%29=x%5E2-6x%2B9
So now our problem looks like this:
%28x-3%29%5E2=12
Next take the square root of both sides remember that the right side will be
plus or minus the square root
sqrt%28%28x-3%29%5E2%29=%28plus_minus%29sqrt%2812%29
x-3=%28plus_minus%29sqrt%2812%29
Finally solve for x
x=3-sqrt%2812%29
and
x=3%2Bsqrt%2812%29
These are the TWO answers for x