SOLUTION: Jack is twice as old as Jill.In 2 years, Jack will be four times as old as Jill was 9 years ago. How old are they now?

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Question 1153387: Jack is twice as old as Jill.In 2 years, Jack will be four times as old as Jill was 9 years ago. How old are they now?
Found 2 solutions by josgarithmetic, MathLover1:
Answer by josgarithmetic(39615) About Me  (Show Source):
You can put this solution on YOUR website!
system%28y=2x%2Cy%2B2=4%28x-9%29%29


2x%2B2=4x-36
38=2x
x=19------------------Jill is 19 and Jack is 38.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

Jack is twice as old as Jill.In 2 years, Jack will be four times as old as Jill was 9 years ago.
let Jack's age be x and Jill's age y
if Jack is twice as old as Jill, we have
x=2y ......eq.1

if in 2 years, Jack will be four+times as old as Jill was 9 years ago, we have
x%2B2=4%28y-9%29
x=4y-36-2
x=4y-38.......eq.2
from eq.1 and eq.2 we have,
2y=4y-38
38=4y-2y
38=2y
y=19
go to
x=2y ......eq.1, substitute y
x=2%2A19
x=38
Jack is 38 years old now and Jill is 19 years old now