SOLUTION: Shirley is 21 years older than Laura. In six years, Shirley will be twice as old as Laura. How old are they now? For my word problem I have S=Shirley and L=Laura. So far I hav

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Question 861307: Shirley is 21 years older than Laura. In six years, Shirley will be twice as old as Laura. How old are they now?
For my word problem I have S=Shirley and L=Laura. So far I have S=L+21 and right under it, S+6=2(L+21) , I may be wrong but can you still check my work and that's all I have down because I'm confused about the other part. Please help me and thank you for your hard work.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You're confusing yourself with the second part.
Don't use the information from the first equation in the second equation.
Your equations need to be independent.
Just go by what the problem states.
In six years, Shirley will be S%2B6 years old.
In six years, Laura will be L%2B6 years old.
In six years, Shirley will be twice as old as Laura.
S%2B6=2%28L%2B6%29
Now that's the second equation.
Together with the first equation,
S=L%2B21
they form a linear system.
Now solve it by substituting for S in the previous equation .
Repost if you still need help.