document.write( "Question 698270: John is 6 years older than his brother. He will be twice as old as his brother in 4 years. How old is John now. \r
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Algebra.Com's Answer #430565 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+a+\"$ = John's age now
\n" ); document.write( "Let $\"+b+\"$ = his Brother's age now
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+=+b+%2B+6+\"$
\n" ); document.write( "(2) $\"+a+%2B+4+=+2%2A%28+b+%2B+4+%29+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+b+%2B+6+%2B+4+=+2%2A%28+b+%2B+4+%29+\"$
\n" ); document.write( "(2) $\"+b+%2B+10+=+2b+%2B+8+\"$
\n" ); document.write( "(2) $\"+b+=+10+-+8+\"$
\n" ); document.write( "(2) $\"+b+=+2+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+a+=+b+%2B+6+\"$
\n" ); document.write( "(1) $\"+a+=+2+%2B+6+\"$
\n" ); document.write( "(1) $\"+a+=+8+\"$
\n" ); document.write( "John is 8 yrs old
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+a+%2B+4+=+2%2A%28+b+%2B+4+%29+\"$
\n" ); document.write( "(2) $\"+8+%2B+4+=+2%2A%28+2+%2B+4+%29+\"$
\n" ); document.write( "(2) $\"+12+=+2%2A6+\"$
\n" ); document.write( "(2) $\"+12+=+12+\"$
\n" ); document.write( "OK \n" ); document.write( "

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