Question 891965
Set x = Sarah's current age
Set y = Linda's current age
Sarah's age 6 years ago was (x-6)
Linda's age 6 years ago was (y-6)
x = 2y
(x-6)=4(y-6)
Now substitute 2y for x in the equation above
((2y)-6)=4(y-6)
2y-6 = 4y - 24
add -4y to each side
 -2y - 6 = -24
add 6 to each side
 -2y = -18
divide each side by -2
 y = 9
Since x = 2y, x = 18
Sarah is currently 18 and Linda is 9
Six years ago they were 12 and 3
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I am not sure what M'techer is thinking.