document.write( "Question 147808: My question is: Write the equation for the ellipse whose center is the origin, has a horizontal major axis length of 12 and passses through the point (-4,2).
\n" ); document.write( "I need help with this, since the horizontal axis is at the origin I get that the foci is (-6,0) and (6,0). I find that the equation will be \"%28x%5E2%2F36%29%2B%28y%5E2%2Fb%5E2%29=1\" but I am having trouble finding what \"b%5E2\" equals. Can you help me?
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Algebra.Com's Answer #108203 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
SOLUTION BY EDWIN\r
\n" ); document.write( "\n" ); document.write( " My question is: Write the equation for the ellipse whose center is the origin, has a horizontal major axis length of 12 and passses through the point (-4,2).
\n" ); document.write( "I need help with this, since the horizontal axis is at the origin I get that the foci is (-6,0) and (6,0). I find that the equation will be \"%28x%5E2%2F36%29%2B%28y%5E2%2Fb%5E2%29=1\" but I am having trouble finding what \"b%5E2\" equals. Can you help me?\r
\n" ); document.write( "\n" ); document.write( "Go back and look at the problem to see what if anything you haven't used. Here's what you haven't used:\r
\n" ); document.write( "\n" ); document.write( ">>...passses through the point (-4,2)...<<\r
\n" ); document.write( "\n" ); document.write( "So you see that all you need do is plug the point (-4,2) into
\n" ); document.write( "\"%28x%5E2%2F36%29%2B%28y%5E2%2Fb%5E2%29=1\" and solve for b.\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2F36%29%2B%28y%5E2%2Fb%5E2%29=1\"
\n" ); document.write( "\"%28%28-4%29%5E2%2F36%29%2B%28%282%29%5E2%2Fb%5E2%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"16%2F36%2B4%2Fb%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "\"4%2F9%2B4%2Fb%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "Clear of fractions by multiplying thru by \"9b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"9b%5E2%2A4%2F9%2B9b%5E2%2A4%2Fb%5E2=9b%5E2%2A1\"
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\n" ); document.write( "\"cross%289%29b%5E2%2A4%2Fcross%289%29%2B9cross%28b%5E2%29%2A4%2Fcross%28b%5E2%29=9b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"4b%5E2%2B36=9b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"36=5b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"36%2F5=b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "That's an ugly answer, but it is correct. So
\n" ); document.write( "the equation of the ellipse in standard form is\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2F36%2By%5E2%2F%2836%2F5%29=1\"\r
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\n" ); document.write( "\n" ); document.write( "Here is its graph:\r
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "\n" ); document.write( "But if you don't necessarily have to have it in standard
\n" ); document.write( "form, you can simplify it.\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2F36%2By%5E2%2F%2836%2F5%29=1\"\r
\n" ); document.write( "\n" ); document.write( "Multiply top and bottom of the second fraction by \"5\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2F36%2B5y%5E2%2F%285%2A%2836%2F5%29%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2F36%2B5y%5E2%2F%28cross%285%29%2A%2836%2Fcross%285%29%29%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2F36%2B5y%5E2%2F36=1\"\r
\n" ); document.write( "\n" ); document.write( "Then multiply through by \"36\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B5y%5E2=36\"
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\n" ); document.write( "Edwin\r
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