document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=31888>Question 31888</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is on a take home assingment.<BR>\n" );
document.write( "Question: Which equation describes an allipse?\r<BR>\n" );
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document.write( "(A) -3x^2-7x-3y^2+2y-9=0\r<BR>\n" );
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document.write( "(B) 2x^2-7x+4y^2-9y=-13\r<BR>\n" );
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document.write( "(C) 5y^2-7y-12x^2-3x+2=0\r<BR>\n" );
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document.write( "(D) 2y^2-7x-9y=-1\r<BR>\n" );
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document.write( "Thank you very much!!!!!!!!!!!!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #18484 by </B><A HREF=/tutors/aboutme.mpl?userid=mukhopadhyay><B>mukhopadhyay(490)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mukhopadhyay><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=18484\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Answer is C.<BR>\n" );
document.write( "5y^2-7y-12x^2-3x+2=0 <BR>\n" );
document.write( "=>5(y-7/10)^2-12(x+3/24)^2=-2+49/20+9/288 (Right side is +ve, it is an ellipse)\r<BR>\n" );
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document.write( "-3x^2-7x-3y^2+2y-9=0<BR>\n" );
document.write( "=>3x^2+7x+3y^2-2y=-9<BR>\n" );
document.write( "=>3(X+7/6)^2+3(Y-2/6)^2=-9+49/12+4/12 (Right side is -ve, so cannot be ellipse)<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2x^2-7x+4y^2-9y=-13 <BR>\n" );
document.write( "=>2(x-7/4)^2+4(y-9/8)^2=-13+49/8+81/16 (is -ve, so cannot be ellipse)<BR>\n" );
document.write( "..<BR>\n" );
document.write( "The last equation represents parabola </SPAN>\n" );
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