document.write( "Question 829538: Jill is 12 years older than jack. IN 8 yeras she will be three times his age. How old is Jack? \n" ); document.write( "
Algebra.Com's Answer #499946 by Fombitz(32388)\"\" \"About 
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Let \"A\" be Jill's age.
\n" ); document.write( "Let \"B\" be Jack's age.
\n" ); document.write( "1.\"A=B%2B12\"
\n" ); document.write( "In 8 years, Jill will be A+8, I assume you mean 3 times his age right now (because otherwise it doesn't work)
\n" ); document.write( "2.\"A%2B8=3B\"
\n" ); document.write( "Substitute eq. 1 into eq. 2,
\n" ); document.write( "\"B%2B12%2B8=3B%2B24\"
\n" ); document.write( "\"B%2B20=3B\"
\n" ); document.write( "\"2B=20\"
\n" ); document.write( "\"B=10\"
\n" ); document.write( "From eq. 1,
\n" ); document.write( "\"A=10%2B12\"
\n" ); document.write( "\"A=22\"
\n" ); document.write( "Jack is 10 and Jill is 22 years old.
\n" ); document.write( "
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