document.write( "Question 469144: My uncle is now 21 years older than me. In 8 years, he will be twice as old as my age. What is our present age? \n" ); document.write( "

Algebra.Com's Answer #321894 by Tatiana_Stebko(1539) $\"\"$ $\"About$

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Let x is my present age
\n" ); document.write( "Let y is my uncle present age
\n" ); document.write( "My uncle is now 21 years older than me, then $\"y-x=21\"$
\n" ); document.write( "In 8 years I'll be $\"x%2B8\"$ years old, my uncle will be $\"y%2B8\"$ years old, and he will be twice as old as my age, so $\"y%2B8=2%28x%2B8%29\"$
\n" ); document.write( "The system:
\n" ); document.write( " $\"system%28y-x=21%2Cy%2B8=2%28x%2B8%29%29\"$
\n" ); document.write( " $\"system%28y=21%2Bx%2C21%2Bx%2B8=2x%2B16%29\"$
\n" ); document.write( " $\"x-2x=16-21-8\"$
\n" ); document.write( " $\"-x=-13\"$
\n" ); document.write( " $\"x=13\"$ is my present age
\n" ); document.write( " $\"y=21%2B13=34\"$ is my uncle present age \n" ); document.write( "

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