document.write( "Question 900867: I'm twice the age you had when i had the age you have and when you'll be my age, sum of our ages will be 72. What age are we \n" ); document.write( "

Algebra.Com's Answer #546245 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I'll say:
\n" ); document.write( "A's age = $\"+a+\"$
\n" ); document.write( "B's age = $\"+b+\"$
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\n" ); document.write( "I will also say that the problem starts
\n" ); document.write( "off talking about A
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\n" ); document.write( "\" When I had the age you have \" means
\n" ); document.write( "when A's age = $\"+b+\"$
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\n" ); document.write( "How old was B then?
\n" ); document.write( "The difference in their ages never changes, so
\n" ); document.write( "B was $\"+b+-+%28+a++-+b+%29+=+2b+-+a+\"$
\n" ); document.write( "-----------------------------
\n" ); document.write( "it says A is presently twice that age, so
\n" ); document.write( "(1) $\"+a+=+2%2A%28+2b+-+a+%29+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "\" and when you'll be my age \" means B's
\n" ); document.write( "age = $\"+a+\"$
\n" ); document.write( "At that time, A's age will be $\"+a+%2B+%28+a+-+b+%29+=+2a+-+b+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "The sum of these ages is:
\n" ); document.write( "(2) $\"+2a+-+b+%2B+a+=+72+\"$
\n" ); document.write( "----------------------
\n" ); document.write( "(1) and (2) have 2 unknowns, so it's solvable
\n" ); document.write( "(1) $\"+a+=+2%2A%28+2b+-+a+%29+\"$
\n" ); document.write( "(1) $\"+a+=+4b+-+2a+\"$
\n" ); document.write( "(1) $\"+3a+=+4b+\"$
\n" ); document.write( "(1) $\"+b+=+%28+3%2F4+%29%2Aa+\"$
\n" ); document.write( "--------------------
\n" ); document.write( "(2) $\"+2a+-+b+%2B+a+=+72+\"$
\n" ); document.write( "(2) $\"+3a+-+b+=+72+\"$
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+3a+-+%283%2F4%29%2Aa+=+72+\"$
\n" ); document.write( "(2) $\"+12a+-+3a+=+288+\"$
\n" ); document.write( "(2) $\"+9a+=+288+\"$
\n" ); document.write( "(2) $\"+a+=+32+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+b+=+%28+3%2F4+%29%2Aa+\"$
\n" ); document.write( "(1) $\"+b+=+%28+3%2F4+%29%2A32+\"$
\n" ); document.write( "(1) $\"+b+=+24+\"$
\n" ); document.write( "-----------------
\n" ); document.write( "A is 32
\n" ); document.write( "B is 24
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\n" ); document.write( "check:
\n" ); document.write( "\" when i had the age you have \"
\n" ); document.write( "( When A was 24 )
\n" ); document.write( "How old was B then?
\n" ); document.write( "B was $\"+24+-+%28+32+-+24+%29+=+24+-+8+\"$
\n" ); document.write( " $\"+24+-+8+=+16+\"$
\n" ); document.write( "------------------
\n" ); document.write( "A is twice that age, or $\"+A+=+32+\"$
\n" ); document.write( "correct
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\n" ); document.write( "When B will be 32, and A will be
\n" ); document.write( " $\"+32+%2B+%28+32+-+24+%29+=+40+\"$ , the sum
\n" ); document.write( "of their age will be 72
\n" ); document.write( " $\"+32+%2B+40+=+72+\"$
\n" ); document.write( "correct again
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\n" ); document.write( "Hope it's not confusing\r
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