document.write( "Question 94181This question is from textbook
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\n" ); document.write( "x^2/25 + y^2/36 = 1
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Algebra.Com's Answer #68580 by Edwin McCravy(20054) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Can someone also tell me What are (a) the x-intercepts, \r\n" );
document.write( "(b) the y-intercepts and (c) the foci of the ellipse\r\n" );
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document.write( "(a)_________\r\n" );
document.write( "(b)_________\r\n" );
document.write( "(c)_________\r\n" );
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document.write( "Principles you need to learn about the two forms of ellipses.\r\n" );
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document.write( "What is important at first is to observe whether the number\r\n" );
document.write( "underneath the x² is greater than or less than the number\r\n" );
document.write( "undernesth the y².  The larger of these is always a² amd the\r\n" );
document.write( "smaller one is always b². \r\n" );
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document.write( "Rule 1.\r\n" );
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document.write( "  where \r\n" );
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document.write( "represents an ellipse that looks like this ( \r\n" );
document.write( "without the pointy thingy.\r\n" );
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document.write( "x-intercepts (a,0) and (-a,0) \r\n" );
document.write( "y-intercepts (0,b) and (0,-b)\r\n" );
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document.write( "Now to find the foci, first you must\r\n" );
document.write( "calculate c by the formula\r\n" );
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document.write( " = ±\r\n" );
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document.write( "for the x-values of the foci.\r\n" );
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document.write( "So the foci are (-c,0) and (c,0).\r\n" );
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document.write( "Rule 2.\r\n" );
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document.write( "  where \r\n" );
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document.write( "represents an ellipse that is shaped like a zero 0 \r\n" );
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document.write( "x-intercepts (b,0) and (-b,0) \r\n" );
document.write( "y-intercepts (0,a) and (0,-a)\r\n" );
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document.write( "Now to find the foci, first you must\r\n" );
document.write( "calculate c by the formula\r\n" );
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document.write( " = ±\r\n" );
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document.write( "for the x-values of the foci.\r\n" );
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document.write( "So the foci are (0,c) and (0,-c).\r\n" );
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document.write( "Yours here is the second case since the number\r\n" );
document.write( "under the y² is greater than the number under \r\n" );
document.write( "the x²:\r\n" );
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document.write( "so we use rule 2.\r\n" );
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document.write( " so \r\n" );
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document.write( " so \r\n" );
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document.write( "  since \r\n" );
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document.write( "represents an ellipse that is shaped like a zero 0 \r\n" );
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document.write( "x-intercepts (5,0) and (-5,0) \r\n" );
document.write( "y-intercepts (0,6) and (0,-6)\r\n" );
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document.write( "Now to find the foci, first you must\r\n" );
document.write( "calculate c by the formula\r\n" );
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document.write( " = ± = ± = ±\r\n" );
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document.write( "or about ±3.3\r\n" );
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document.write( "for the x-values of the foci.\r\n" );
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document.write( "So the foci are (0,) and (0,),\r\n" );
document.write( "or about (0,3.3) and (0,-3.3)\r\n" );
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document.write( "Here's the graph. The foci are marked with little short lines:\r\n" );
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document.write( "Edwin

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