document.write( "Question 645536: mark is y years old. in five years time aoife will be twice as old as mark and daniel will be two years younger than aoife is now. write an expression in y for the sum of the 3 ages now. show workings please :) \n" ); document.write( "
Algebra.Com's Answer #405576 by ankor@dixie-net.com(22740)\"\" \"About 
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mark is y years old.
\n" ); document.write( "In five years time Aoife will be twice as old as Mark
\n" ); document.write( "A + 5 = 2(y+5)
\n" ); document.write( "A + 5 = 2y + 10
\n" ); document.write( "A = 2y + 10 - 5
\n" ); document.write( "A = 2y + 5
\n" ); document.write( ":
\n" ); document.write( "and Daniel will be two years younger than Aoife is now.
\n" ); document.write( "d + 5 = A - 2
\n" ); document.write( "d = A - 2 - 5
\n" ); document.write( "d = A - 7
\n" ); document.write( "Replace A with (2y+5)
\n" ); document.write( "d = (2y+5) - 7
\n" ); document.write( "d = 2y - 2
\n" ); document.write( ":
\n" ); document.write( "write an expression in y for the sum of the 3 ages now.
\n" ); document.write( "Sum = y + A + d
\n" ); document.write( "replace A and d with expressions derived above:
\n" ); document.write( "S = y + (2y+5) + (2y-2)
\n" ); document.write( "S = y + 4y + 3
\n" ); document.write( "S = 5y + 3 is the sum of the three ages \n" ); document.write( "
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