document.write( "Question 43057: \"Graph the equation, then choose the correct coordinates of the foci. Keep the graphs as they may be asked for at a later time. y^2= 5x^2+25.\" I keep trying to graph equations like this and find the foci, but the answers I get are never one of the answer choices. For this one I did:
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document.write( "y^2= 5x^2+25
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document.write( "y^2-5x^2= 25
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document.write( "(y^2-5x^2)/-5=25/-5\r
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document.write( "-1/5(y^2/-5-x^2)=-5/-5
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document.write( "y^2/25+x^2/5=1\r
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document.write( "y^2/(5)^2+x^2/(square root 5)^2=1\r
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document.write( "After that I had my x and y intercepts so I made my graph and tried to find the foci.\r
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document.write( "b^2=a^2-c^2\r
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document.write( "square root 5^2= 5^2-c^2\r
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document.write( "5= 25-c^2\r
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document.write( "5-25= -c^2\r
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document.write( "20= c^2\r
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document.write( "square root 20= c
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document.write( "I'd appreciate your help. These graphs have really been frustrating me. Please me know what I'm doing wrong. Thanx! \n" );
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Algebra.Com's Answer #28077 by psbhowmick(878)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "or \n" ); document.write( "or \n" ); document.write( "or \n" ); document.write( "or \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "As simple as that! \n" ); document.write( "Don't make the algebra complex. \n" ); document.write( "Divide both sides by 25 (to make the term on right side = 1). \n" ); document.write( "This is a hyperbola and not an ellipse. \n" ); document.write( "You derived a wrong equation resulting in wrong type of conic (you got ellipse).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Comparing with standard equation of hyperbola \n" ); document.write( " \n" ); document.write( "where '2a' and '2b' are the lengths of transverse and conjugate axes respectively we have \n" ); document.write( "a = 5, b = \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now, eccentricity is \n" ); document.write( "or \n" ); document.write( "or \n" ); document.write( "or \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The foci are at (0,ae) and (0,-ae) i.e. (0, \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " |