document.write( "Question 1147629: In 10 years from now, my age will be the square of my age 10 years ago. How old am I? \n" ); document.write( "

Algebra.Com's Answer #768970 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Your equation is\r\n" );
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document.write( "    a + 10 = (a-10)^2\r\n" );
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document.write( "Simplify and solve\r\n" );
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document.write( "    a + 10 = a^2 - 20a + 100\r\n" );
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document.write( "    a^2 - 21a + 90 = 0\r\n" );
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document.write( "    (a-15)*(a-6) = 0.\r\n" );
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document.write( "Of the two roots, only \"15\" allows to subtract 10 and obtain the positive age ten years ago.\r\n" );
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document.write( "Hence, the problem has a unique ANSWER.  Your age is 15 years.\r\n" );
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