Graphing x^2 + y^2 = 81

Bladesofhalo

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Sep 18, 2006
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How would you graph x[sup:35wqnwfu]2[/sup:35wqnwfu] + y[sup:35wqnwfu]2[/sup:35wqnwfu] = 81. Do I have to solve for y like usual?
 

stapel

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I would suspect that you're supposed to recognise the form of a circle equation, and note that this is a circle centered at the origin, with a radius of nine units. :wink:

Eliz.
 

Loren

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Aug 28, 2007
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Solving for y will work. If you do so, you will be able to plot several points which will produce the desired circle. Just remember that when you solve for y you will get a \(\displaystyle \pm\sqrt{something}\)
 
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