document.write( "Question 723537: the graph of the equation below is an ellipse. How long is the major axis of the ellipse given by the equation? (x+7)^2 5^2 + (y-4)^2 8^2= 1 \n" ); document.write( "
Algebra.Com's Answer #443212 by KMST(5328)\"\" \"About 
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If the equation is really \"%28x%2B7%29%5E2+%2A5%5E2+%2B+%28y-4%29%5E2%2A+8%5E2=+1\" the major and minor axes are not very long.
\n" ); document.write( "\"graph%28300%2C300%2C-8%2C1%2C-2%2C8%2C25%28x%2B7%29%5E2%2B64%28y-4%29%5E2%3C=1%29\"
\n" ); document.write( "When \"y=4\" the second term is \"%284-4%29%5E2%2A+8%5E2=0%5E2%2A+8%5E2=0%2A+8%5E2=0\"
\n" ); document.write( "and you get the extreme values for x:
\n" ); document.write( "\"%28x%2B7%29%5E2+%2A5%5E2+=+1\" --> \"%28x%2B7%29%5E2+=+1%2F5%5E2\" --> \"x%2B7=-1%2F5\" or \"x%2B7=1%2F5\" ,
\n" ); document.write( "which can be summarized as \"x=-7+%2B-+1%2F5\"
\n" ); document.write( "So the horizontal axis would be \"2%2F5\" in length, the distance between those two extreme points. That is the major axis, the longest one.
\n" ); document.write( "The ends of the shorter vertical axis can be found for \"x=-7\" where \"y=4+%2B-+1%2F8\" ,
\n" ); document.write( "which makes the length of that axis \"2%281%2F8%29=1%2F4\" .
\n" ); document.write( "
\n" ); document.write( "If the equation was \"%28x%2B7%29%5E2%2F5%5E2+%2B+%28y-4%29%5E2%2F8%5E2=+1\" instead,
\n" ); document.write( "the ends of the horizontal axis would still be at \"y=4\" ,
\n" ); document.write( "but with \"x=-7+%2B-+5\" ,
\n" ); document.write( "and the ends of the vertical axis would still be at \"x=-7\" ,
\n" ); document.write( "but with \"y=4+%2B-+8\" .
\n" ); document.write( "The length of the axes would be
\n" ); document.write( "\"2%2A5=10\" for the shorter, horizontal, minor axis,
\n" ); document.write( "and \"2%2A8=16\" for the longer, vertical, major axis.
\n" ); document.write( "\"graph%28300%2C300%2C-16%2C4%2C-6%2C14%2C%28x%2B7%29%5E2%2F25%2B%28y-4%29%5E2%2F64%3C=1%29\"
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