First plot the 4 points on graph paper:\r\n" );
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document.write( "By looking at the graph we can easily see that a circle can be drawn\r\n" );
document.write( "through those 4 points and the center will be (h,k) = (4,3) and\r\n" );
document.write( "the radius will be r=2. Like this:\r\n" );
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document.write( "First we get the center-radius form, which is\r\n" );
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document.write( "Substituting (h,k) = (4,3) and r=2\r\n" );
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document.write( "That's the center-radius form.\r\n" );
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document.write( "To get the general form which is\r\n" );
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document.write( "We start with the center-radius form which we just found,\r\n" );
document.write( "remove the parentheses by squaring the binomials, collect \r\n" );
document.write( "like terms, get 0 on the right, and arrange in the \r\n" );
document.write( "general form:\r\n" );
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document.write( "If you know some short-cuts you can skip some of those steps.\r\n" );
document.write( "But be careful.\r\n" );
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document.write( "Edwin
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document.write( "![\"\"](\"/images/stars/stars-13.gif\")
