document.write( "Question 87278: John is 12 years younger than Mary. Mery's age in 8 years will exceeed twice John's age 3 year's ago by 4 years. How old is each now? \n" ); document.write( "
Algebra.Com's Answer #63216 by longjonsilver(2297)\"\" \"About 
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first define ages:
\n" ); document.write( "Let x = john's age NOW
\n" ); document.write( "Let y = mery's age NOW\r
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\n" ); document.write( "\n" ); document.write( "so: john is 12 years younger than mery --> x=y-12
\n" ); document.write( "--> y = x+12\r
\n" ); document.write( "\n" ); document.write( "and: mery's age in 8 years will exceeed twice john's age 3 year's ago by 4 years --> y+8 is Mery's age in 8 years time. John's age 3 years ago was x-3. So,
\n" ); document.write( "y+8 = 2(x-3) + 4
\n" ); document.write( "--> y+8 = 2x-6 + 4
\n" ); document.write( "y+8 = 2x-2
\n" ); document.write( "y = 2x-10\r
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\n" ); document.write( "\n" ); document.write( "So we know that y= both of the Right hand terms so those 2 right hand terms must be the same number:\r
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\n" ); document.write( "\n" ); document.write( "x+12 = 2x - 10
\n" ); document.write( "12 = x - 10
\n" ); document.write( "22 = x\r
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\n" ); document.write( "\n" ); document.write( "if x=22
\n" ); document.write( "then y = x+12
\n" ); document.write( "--> y = 22+12
\n" ); document.write( "--> y = 34\r
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\n" ); document.write( "\n" ); document.write( "You try the other one\r
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\n" ); document.write( "\n" ); document.write( "cheers
\n" ); document.write( "Jon
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