document.write( "Question 1147216: Bob is five years older than his brother Billy. The product of their ages is 414. How old are Bob and Billy. \n" ); document.write( "

Algebra.Com's Answer #768523 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "    x*(x+5) = 414.\r\n" );
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document.write( "    x^2 + 5x - 414 = 0.\r\n" );
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document.write( "Solve this quadratic equation by any way you can / (you know).\r\n" );
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document.write( "Try to guess two factors of the number 414 such that\r\n" );
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document.write( "    x * y = 414  and x and y  differ by 5.\r\n" );
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document.write( "414 has factors\r\n" );
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document.write( "    2  and  207\r\n" );
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document.write( "    2*3= 6 and 69\r\n" );
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document.write( "    2*3*3 = 18 and 23   <<<---===   O-o-p-s !   these factors are PERFECTLY good (!)\r\n" );
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document.write( "Check.   18*23 = 414  and  23 - 18 = 5.\r\n" );
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document.write( "ANSWER.  18 and 23 years old.\r\n" );
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