SOLUTION: Please help me solve this equation Thank You ~ The sum of the present ages of Ali and Salimah is 18 years.In 6 years time Ali will be twice as old as Salimah .Find their presen

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Question 546805: Please help me solve this equation Thank You ~
The sum of the present ages of Ali and Salimah is 18 years.In 6 years time Ali will be twice as old as Salimah .Find their present ages .
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let A = Ali's present age and S = Salimah's present age.
1) A+S = 18 "The sum of the present ages...is 18 years".
2) A+6 = 2(S+6) "In 6 year's time Ali wil be twice as old as Salimah".
Rewrite equation 1) as A = 18-S and substitute into equation 2), then solve for S.
2a) (18-S)+6 = 2(S+6) Simplify.
2b) 24-S = 2S+12 Add S to both sides.
2c) 24 = 3S+12 Subtract 12 from both sides.
2d) 12 = 3S Now divide by 3.
2e) S = 4 and A = 18-4 = 14.
Salimah is 4 years old and Ali is 14 years old.