document.write( "Question 1172287: Frank is eight years older than his sister, Amy. In three years he
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Algebra.Com's Answer #797259 by ikleyn(52792) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let x be the sister current age.\r\n" );
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document.write( "Then  Frank is (x+8) years old.\r\n" );
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document.write( "In 3 years,  the sister age will be (x+3) years,\r\n" );
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document.write( "while Frank will be (x(x+8) + 3) = (x+11) years old.\r\n" );
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document.write( "The condition says that\r\n" );
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document.write( "    x+11 = 2*(x+3).\r\n" );
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document.write( "Simplify and solve\r\n" );
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document.write( "    x + 11 = 2x + 6\r\n" );
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document.write( "    11 - 6 = 2x - x\r\n" );
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document.write( "       5   = x\r\n" );
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document.write( "ANSWER.  The sister is 5 years old.  Frank is 5+8 = 13 years old.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The setup equation in the post by @josgarithmetic $\"highlight%28%28x%2B8%29%2B3=2%28x%2B8%29%29\"$ is TOTALLY WRONG $\"highlight%28cross%28%28x%2B8%29%2B3=2%28x%2B8%29%29%29\"$
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