Question 880809
 <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi
Let x represent tom's age and y Tim's age    
x + y = 21  0r  y = {{{21-x}}}
In 3 years...
x + 3 = 2[(21-x)+3]
x + 3 = 2[24-x]
x + 3 = 48 - 2x
  3x = 45
   x = 15, Tom's age.  Tim is 6  {{{21-15}}}
CHECKING our answer***In 3 years
  18 = 2•9
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