document.write( "Question 1141053: For what values of x will (..., x+1, x+5, 3x+2, ...) be a geometric sequence? \n" ); document.write( "

Algebra.Com's Answer #761594 by Edwin McCravy(20056) $\"\"$ $\"About$

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For what values of x will (...,x+1, x+5, 3x+2, ...) be a geometric sequence?
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It will be a geometric sequence with common ratio r if but only if,\r\n" );
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document.write( "1. the second term x+5 is r times the first term x+1, that is,\r\n" );
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document.write( "      x+5 = r(x+1)\r\n" );
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document.write( "AND\r\n" );
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document.write( "2. the third term 3x+2 is r times the second term x+5, that is,\r\n" );
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document.write( "     3x+2 = r(x+5)\r\n" );
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document.write( "So we have the system of two equations in two unknowns x and r:\r\n" );
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document.write( "Solve the first equation for r:\r\n" );
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document.write( "Substitute that for r in the second equation:\r\n" );
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document.write( "Multiply both sides by (x+1)\r\n" );
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document.write( "Oh darn! That doesn't factor, so we must use the quadratic formula\r\n" );
document.write( "(Are you sure you copied it right?)\r\n" );
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document.write( "with a=2, b=-5, c=-23\r\n" );
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document.write( "Edwin

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