document.write( "Question 565392: How do you write an equation for this table?
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Algebra.Com's Answer #365780 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
X=1, 2, 3, 4, 5, 6, 7
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document.write( "If you look at the Y-values, you will discover that\r\n" );
document.write( "each one is one less than the corresponding term \r\n" );
document.write( "of this sequence:\r\n" );
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document.write( "2, 4, 8, 16, 32, 64, 128\r\n" );
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document.write( "which are the 1st, 2nd, 3rd, 4th, etc. powers of 2.\r\n" );
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document.write( "So the X-th term of the given sequence is 1 less than\r\n" );
document.write( "2X.  So the equation you're looking for is:\r\n" );
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document.write( "Y = 2X - 1\r\n" );
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document.write( "You just have to be observant and familiar with the\r\n" );
document.write( "various powers of small numbers to do problems like these.\r\n" );
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document.write( "Edwin
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