document.write( "Question 238587: he is 21 years old\r
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Algebra.Com's Answer #175351 by scott8148(6628)\"\" \"About 
You can put this solution on YOUR website!
X-10= age of eric 10 years ago
\n" ); document.write( "Eric is now 3 times as old as he was 10 years ago: 3(X-10)
\n" ); document.write( "X is his age now\r
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\n" ); document.write( "\n" ); document.write( "3(X-10)=X
\n" ); document.write( "3X-30=X
\n" ); document.write( "2X=30
\n" ); document.write( "X=15
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