document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=216624>Question 216624</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 9x^2 + 16y^2 - 18x + 64y - 71 = 0<BR>\n" );
document.write( "find the coordinates of the center.\r<BR>\n" );
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document.write( "a)(1,2)<BR>\n" );
document.write( "b)(1,-2)<BR>\n" );
document.write( "c)(-1,2)<BR>\n" );
document.write( "d)(-2,1) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #163563 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=163563\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 9x^2 -18x  +  16y^2 +64y = 71<BR>\n" );
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document.write( "9(x^2 -2x ) + 16(y^2 +4y ) = 71,,,complete  the  squares  remembering  the  last  term  = (2nd  term / 2) squared,,,,,and  add  compensating  amt  to  opposite  side  of  eqn<BR>\n" );
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document.write( "9(x^2 -2x +1) +16(y^2 +4y+4) = 71 +(9*1) + (16*4) = 144<BR>\n" );
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document.write( "9(x-1)^2 +16(y+2)^2 =144,,,,   divide  by  144<BR>\n" );
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document.write( "(1/16){(x-1)^2}  + (1/9){(y+2)^2} = 1<BR>\n" );
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document.write( "{(x-1)^2} / 16 + {(y+2)^2} / 9 =1,,,,,,,which  is  eqn  for  ellipse<BR>\n" );
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document.write( "Center  is  at  (1,-2),,,,,,,which  is  answer  (b)<BR>\n" );
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