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Old November 4th, 2009, 04:38 PM
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Problem:4x^2 + 4x +y^2 = 0

I graph it and I get an elipse, but I cant figure out how to get it into the form:
\frac{x^2}{a^2} + \frac{y^2}{b^2} =1

I've using the form:

b^2x^x + a^2y^2 = a^2b^2

and setting:

a^2b^2 = -4x

But, nothing came good out of that.

Any suggestions?
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  #2  
Old November 4th, 2009, 05:01 PM
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Originally Posted by Sw0rDz View Post
Problem:4x^2 + 4x +y^2 = 0

I graph it and I get an elipse, but I cant figure out how to get it into the form:
\frac{x^2}{a^2} + \frac{y^2}{b^2} =1

I've using the form:

b^2x^x + a^2y^2 = a^2b^2

and setting:

a^2b^2 = -4x

But, nothing came good out of that.

Any suggestions?
4x^2 + 4x +y^2 = 0

4\left(x^2 + x + \frac{1}{4}\right) + y^2 = 1

4\left(x + \frac{1}{2}\right)^2 + y^2 = 1

\frac{\left(x + \frac{1}{2}\right)^2}{\left(\frac{1}{2}\right)^2} + \frac{y^2}{1^2} = 1
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Old November 4th, 2009, 05:15 PM
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Quote:
Originally Posted by skeeter View Post
4x^2 + 4x +y^2 = 0

4\left(x^2 + x + \frac{1}{4}\right) + y^2 = 1

4\left(x + \frac{1}{2}\right)^2 + y^2 = 1

\frac{\left(x + \frac{1}{2}\right)^2}{\left(\frac{1}{2}\right)^2} + \frac{y^2}{1^2} = 1

Awh!! Thankyou!
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