Hi all. I have a analytic geometry question that I need a bit of help with.(adsbygoogle = window.adsbygoogle || []).push({});

consider the concentric circles with the equations:

[tex]x^2 + y^2 = 9[/tex]

and

[tex]x^2 +y^2 = 4[/tex]

A radius from the center O intersects the inner circle at P and the outer circle at Q. The line paralell to the x-axis through P meets the line parallel to the y-axis through Q at the point R. Prove that R lies on the ellipse

[tex]((x^2)/9) + ((y^2)/4) =1[/tex]

Some of the facts I've established:

the distance from P to Q is 1 for sure. Also, the triagle PQR is a right angle triangle. using the ellipse equation, i know that the distance from the center to the vertex is 3, and that the distance from the center to the focus is the square root of 5.

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# Homework Help: Analytic geometry

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