SOLUTION: Jodie is now 28 years old and Dave is 10 years old. In how many years will Jody be twice as old as Dave? I think this is solved by a simultaneous equation, but don't quite know h

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Question 732669: Jodie is now 28 years old and Dave is 10 years old. In how many years will Jody be twice as old as Dave? I think this is solved by a simultaneous equation, but don't quite know how to set it up. I have drawn a simple two row 9 column table and worked it out to be 8 years but I know it could be done quicker with a simultaneous equation.
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
That will happen in x years. Let's find x.
In x years Jodie will be 28%2Bx years old.
At that time Dave will be 10%2Bx years old.
Jodie will be be twice as old as Dave, so
28%2Bx=2%2A%2810%2Bx%29 --> 28%2Bx=20%2B2x --> 28%2Bx-x-20=20%2B2x-x-20 --> 28-20=2x-x --> 8=x
So in highlight%288%29 years Jodie will be twice as old as Dave.

Verification:
In 8 years Dave will be 10%2B8=18 years old and Jodie will be 28%2B8=36 years old, which is twice as old as 18 years old.