document.write( "Question 23302: The Earth is closest to the sun in January. The closest point, or perihelion, is 1.47 x 10^8km from the sun. The Earth is farthest from the sun in july. The farthest point or Aphelion, is 1.52 x 10^8 km from the sun. Write an equation of the ellipse that models the Earth orbit around the sun. Assume that the centre of the ellipse is at the origin and that the major axis is along the x-axis. \r
\n" ); document.write( "\n" ); document.write( "-------------------------Earth
\n" ); document.write( "Perihelion.___sun_________.Aphelion -----------> assuming this is the ellipse. \n" ); document.write( "
Algebra.Com's Answer #12084 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
I'm going to drop the 10's for the moment and just use 1.47 and 1.52.
\n" ); document.write( "The major axis is 2a = 1.47+1.52 = 2.99
\n" ); document.write( "So, a = 2.99/2 = 1.495 and a^2 = 2.235025
\n" ); document.write( "c=1.495-1.47= 0.025
\n" ); document.write( "To find \"b\" for an ellipse b^2=a^2-c^2
\n" ); document.write( "b^2=2.235025-0.025^2=2.234400
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\n" ); document.write( "Therefore the equation of your ellipse, which has the form
\n" ); document.write( "x^2/a^2 + y^2/b^2 = 1 is
\n" ); document.write( "x^2/(1.495X10)^2 + y^2/[1.494657X10]^2 = 1
\n" ); document.write( "x^2/[2.235025X10^2] + y^2/[2.234400X10^2] = 1
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\n" ); document.write( "Cheers,
\n" ); document.write( "stan H. \n" ); document.write( "
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