document.write( "Question 1197617: Word Problems (Ellipse)\r
\n" ); document.write( "\n" ); document.write( "The planet earth comes closest to the sun at 147 million
\n" ); document.write( "km, and farthest from the sun at 152 million km. Thus,
\n" ); document.write( "its orbit is an ellipse for which the two vertices are 147
\n" ); document.write( "and 152 units away from a particular focus, the sun.
\n" ); document.write( "Find the equation of this ellipse, assuming that the major
\n" ); document.write( "axis is horizontal and the center at the origin. (units to be
\n" ); document.write( "in million km.)
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Algebra.Com's Answer #831008 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "let say the sun is located in focus whose coordinates are (\"0\",\"0\"), -> (\"h%2Bc\",\"k\") and -> (\"h-c\",\"k\")
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\n" ); document.write( " two vertices are \"147\" and \"152\" units away from a particular focus (\"0\",\"0\") (so, left and right from origin)\r
\n" ); document.write( "\n" ); document.write( "vertices are at (\"147\",\"0\") and (\"-152\",\"0\")-> (\"h%2Ba\",\"k\") and (\"h-a\",\"k\")\r
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\n" ); document.write( "\n" ); document.write( " vertices differ \"5+\"units, so the other focus will be \"5\" units left from origin at (\"-5\", \"0\")\r
\n" ); document.write( "\n" ); document.write( "center is half way between: (\"-5%2F2\", \"0\")=(\"-2.5\", \"0\")\r
\n" ); document.write( "\n" ); document.write( "=>\"h=-2.5\", \"k=0\"\r
\n" ); document.write( "\n" ); document.write( "find \"a%5E2\":\r
\n" ); document.write( "\n" ); document.write( "\"h%2Ba=147\"\r
\n" ); document.write( "\n" ); document.write( "\"-2.5%2Ba=147\"\r
\n" ); document.write( "\n" ); document.write( "\"a=147%2B2.5=149.5\"\r
\n" ); document.write( "\n" ); document.write( "\"a%5E2=22350.25\"\r
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\n" ); document.write( "\n" ); document.write( "find \"c%5E2\":\r
\n" ); document.write( "\n" ); document.write( "\"h%2Bc=-5\"\r
\n" ); document.write( "\n" ); document.write( "\"-2.5%2Bc=-5\"\r
\n" ); document.write( "\n" ); document.write( "\"c%5E2=%28-2.5%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"c%5E2=6.25\"\r
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\n" ); document.write( "\n" ); document.write( "find \"b%5E2\":\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2=a%5E2-c%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2=22350.25-6.25\"\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2=22344\"\r
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\n" ); document.write( "\n" ); document.write( "your ellipse is:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B2.5%29%5E2%2F22350.25%2By%5E2%2F22344=1\"\r
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