SOLUTION: If shuanais now 4 years older than her sister. Two years ago, shuanais was three times as old as the sister was. How old is each girl?

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Question 1024331: If shuanais now 4 years older than her sister. Two years ago, shuanais was three times as old as the sister was. How old is each girl?
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Call her and her sister's age NOW, x and y. Then we write
x = y + 4
Two years ago
x - 2 = 3(y - 2)
Now substitute the first equation into the second equation...we get
y+4 - 2 = 3(y - 2)
y + 2 = 3y - 6
8 = 2y and
y = 4
so that
x = 8