document.write( "Question 792278: Laura is 4 years older than her brother. Two years ago Laura was three times as old as her brother. How old are they now?\r
\n" ); document.write( "\n" ); document.write( "I got for my answer 9 Laura and 5 Brother, using (4+b)=3(b-2). I got the brothers age by using 4+b after I put the two equations together and getting b=5 then adding 4 to 5 for Laura and not adding 4 for the brother. But the book says laura is 8 and the brother is 4 \n" ); document.write( "
Algebra.Com's Answer #479949 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Let's do it this way and see what happens, sometimes the book is wrong
\n" ); document.write( ":
\n" ); document.write( " Laura is 4 years older than her brother.
\n" ); document.write( "L = b + 4
\n" ); document.write( " Two years ago Laura was three times as old as her brother.
\n" ); document.write( "L-2 = 3(b-2)
\n" ); document.write( "L - 2 = 3b - 6
\n" ); document.write( "L = 3b - 6 + 2
\n" ); document.write( "L = 3b - 4
\n" ); document.write( "replace L with (b+4)
\n" ); document.write( "b + 4 = 3b - 4
\n" ); document.write( "4 + 4 = 3b - b
\n" ); document.write( "8 = 2b
\n" ); document.write( "b = 8/2
\n" ); document.write( "b = 4 brother's age
\n" ); document.write( ":
\n" ); document.write( "I see what you did here, can be done your way but,
\n" ); document.write( "2 has to be subtracted from both ages
\n" ); document.write( "4+b-2 = 3(b-2)
\n" ); document.write( "b + 2 = 3b - 6
\n" ); document.write( "2 + 6 = 3b - b
\n" ); document.write( " \n" ); document.write( "
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