document.write( "Question 627189: jack is 3 years older then his sister jill. the sum of their ages is 45. how old are jack and jill. \n" ); document.write( "

Algebra.Com's Answer #394759 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = Jack's age now
\n" ); document.write( "Let $\"+b+\"$ = Jill's age now
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+=+b++%2B+3+\"$
\n" ); document.write( "(2) $\"+a+%2B+b+=+45+\"$
\n" ); document.write( "-------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+b+%2B+3+%2B+b+=+45+\"$
\n" ); document.write( "(2) $\"+2b+%2B+3+=+45+\"$
\n" ); document.write( "(2) $\"+2b+=+42+\"$
\n" ); document.write( "(2) $\"+b+=+21+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(2) $\"+a+%2B+b+=+45+\"$
\n" ); document.write( "(2) $\"+a+%2B+21+=+45+\"$
\n" ); document.write( "(2) $\"+a+=+24+\"$
\n" ); document.write( "Jack is 24 and Jill is 21\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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