SOLUTION: Liza is 25 years younger than her mother. After 4 years, her mother's age will be twice as old as her. How old are they?

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Question 1050807: Liza is 25 years younger than her mother. After 4 years, her mother's age will be twice as old as her. How old are they?
Answer by advanced_Learner(501) About Me  (Show Source):
You can put this solution on YOUR website!
L=M-25
2(L+4)=M+4
2L+4=M


M-L=25
M-2L=4
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++1%5Cm+%2B+-1%5Cl+=+25%2C%0D%0A++++1%5Cm+%2B+-2%5Cl+=+4+%29%0D%0A++We'll use substitution. After moving -1*l to the right, we get:
1%2Am+=+25+-+-1%2Al, or m+=+25%2F1+-+-1%2Al%2F1. Substitute that
into another equation:
1%2A%2825%2F1+-+-1%2Al%2F1%29+%2B+-2%5Cl+=+4 and simplify: So, we know that l=21. Since m+=+25%2F1+-+-1%2Al%2F1, m=46.

Answer: system%28+m=46%2C+l=21+%29.