document.write( "Question 66246: Please help sketch the graph and name the conic section with equation:
\n" ); document.write( "4x^2-16x+9y^2+18y=0 So far I have factored out the 4 and 9. What comes next?Thank you
\n" ); document.write( "

Algebra.Com's Answer #47972 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
I'm afraid the other solution that was posted for this problem is incorrect. Anytime you have an equation of a conic section with \"x%5E2\" and \"y%5E2\" with both having positive but unequal coefficients, it will be an ELLIPSE, NOT a PARABOLA. \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "If both coefficients are the same sign with equal coefficients, it will be a CIRCLE. \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "If coefficients are of opposite sign, then it will be a HYPERBOLA. \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "A PARABOLA results when there is an \"x%5E2\" but no \"y%5E2\" or a \"y%5E2\" but no \"x%5E2\". \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "This is the way it should be solved by completing the square:
\n" ); document.write( "\"4x%5E2-16x%2B9y%5E2%2B18y=0\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "You must first factor out the coefficients of x^2 and y^2 like this:
\n" ); document.write( "\"4%28x%5E2-4x%2B____%29%2B9%28y%5E2+%2B2y+%2B+_____%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"4%28x%5E2-4x%2B4%29%2B9%28y%5E2+%2B2y+%2B+1%29=0%2B16%2B9\"
\n" ); document.write( "\"4%28x%5E2-4x%2B4%29%2B9%28y%5E2+%2B2y+%2B+1%29=25\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "This is an ellipse. The standard form for an ellipse is in a form = 1, so divide both sides of the equation by 25 to set it equal to 1.\r
\n" ); document.write( "\n" ); document.write( "\"%284%28x-2%29%5E2%29%2F25+%2B%289%28y%2B+1%29%5E2%29%2F25=25%2F25\"
\n" ); document.write( "\"%284%28x-2%29%5E2%29%2F25+%2B%289%28y%2B+1%29%5E2%29%2F25=1\"\r
\n" ); document.write( "\n" ); document.write( "Finally invert the coefficients of 4 and 9 in order to write this:
\n" ); document.write( "\"%28%28x-2%29%5E2%29%2F%2825%2F4%29+%2B%28%28y%2B+1%29%5E2%29%2F%2825%2F9%29=1\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "That would be standard form for an ellipse! The center is at (2,-1), with the \"radius\" extending \"5%2F2\" units in the x direction, and \"5%2F3\" units in the y direction. \r
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "R^2 at SCC\r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );