document.write( "Question 1209327: Let
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Algebra.Com's Answer #848366 by mccravyedwin(407)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "This is the graph of f(x)\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"%282x+%2B+5%29%2F%28x+-+4%29\"\r\n" );
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document.write( "Substitute y for f(x)\r\n" );
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document.write( "\"y\"\"%22%22=%22%22\"\"%282x+%2B+5%29%2F%28x+-+4%29\"\r\n" );
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document.write( "Interchange x and y\r\n" );
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document.write( "\"x\"\"%22%22=%22%22\"\"%282y+%2B+5%29%2F%28y+-+4%29\"\r\n" );
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document.write( "Solve for y:\r\n" );
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document.write( "\"x%28y-4%29\"\"%22%22=%22%22\"\"2y+%2B+5\"\r\n" );
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document.write( "\"xy-4x\"\"%22%22=%22%22\"\"2y+%2B+5\"\r\n" );
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document.write( "\"xy-2y\"\"%22%22=%22%22\"\"5%2B4x\"\r\n" );
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document.write( "\"y%28x-2%29\"\"%22%22=%22%22\"\"5%2B4x\"\r\n" );
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document.write( "\"y\"\"%22%22=%22%22\"\"%285%2B4x%29%2F%28x-2%29\"\r\n" );
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document.write( "Replace y by f-1(x):\r\n" );
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document.write( "\"matrix%281%2C2%2Cf%5E%28-1%29%2C%22%28x%29%22%29\"\"%22%22=%22%22\"\"%285%2B4x%29%2F%28x-2%29\"\r\n" );
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document.write( "The green graph below is the graph of f-1(x), with the point (1,-9)\r\n" );
document.write( "circled which shows the answer -9:\r\n" );
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document.write( "\"matrix%281%2C2%2Cf%5E%28-1%29%2C%22%281%29%22%29\"\"%22%22=%22%22\"\"%285%2B4%281%29%29%2F%281-2%29=%285%2B4%29%2F%28-1%29=9%2F%28-1%29=-9\"   <---answer\r\n" );
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document.write( "Edwin
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