<PRE><B>Question 816678</B>
Five years ago, Roel was three times as old as his brother, Tony. In 10 years, he will be 10 years older than Tony. Find their present ages.

 Set r = age of Roel
 Set t = age of Tony

 ( r - 5 ) = 3(t-5)
 ( r + 10 ) = ( t + 10 ) + 10

Simplifying
   r - 5 = 3t - 15
   r + 10 = t + 20

Subtract the bottom equation from the top
     -15 = 2t - 35
Add 35 to each side.
      20 = 2t
      10 = t
Substitute 10 for t in the equation r + 10 = t + 20
      r + 10 = 10 + 20
Subtract 10 from each side
      r = 20
To check our answer, substitute 10 for t and 20 for r in the equations
 ( r - 5 ) = 3(t-5)
 ( r + 10 ) = ( t + 10 ) + 10

 ( 20 - 5 ) = 3(10-5) so 15 = 3(5) or 15 = 15
 ( 20 + 10 ) = ( 10 + 10 ) + 10 so 30 = 30

We can say that Roel is 20 and Tony is 10.</PRE>