I'm finding it difficult to solve this question

It's solving quadratic eqaution by completing the square

x^2+6x+1=0

Any help?

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- October 14th 2009, 06:25 AMMistQuadratic Equation
I'm finding it difficult to solve this question

It's solving quadratic eqaution by completing the square

x^2+6x+1=0

Any help? - October 14th 2009, 06:33 AMcraig
Here's how I'd proceed.

When solving the square of a quadratic in the form , first you put into brackets, .

So in the case of your question you get . However, if you multiply out ,you find that you get an extra 9 in your equation, to compensate for this you also place a -9 in your equation, giving you .

A little bit of rearranging should give you , which in turn leads to .

I presume you can continue from here to find the two solutions.

Craig - October 14th 2009, 06:34 AMmasters
Hi Mist,

Step 1: Transpose the constant to the right hand side.

Step 2: Take half the coefficent of the linear term (x), square it, and add the result to both sides of the equation.

Step 3: You have just made the left side a perfect square trinomial.

Step 4: Take the square root of both sides.

I'll bet you can finish up, can't you?