SOLUTION: Robbie is four years older than his sister, Michela. seven years ago, Robbie was three times as old as his sister. How old is Michela now?

Question 821815: Robbie is four years older than his sister, Michela. seven years ago, Robbie was three times as old as his sister. How old is Michela now?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
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x = y + 4
x - 7 = 3(y - 7)
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x = y + 4
x - 7 = 3y - 21
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put the system of linear equations into standard form
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x - y = 4
x - 3y = -14
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copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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answer:
x= robbie = 13
y= michela = 9
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Solve systems of linear equations up to 6-equations 6-variables:
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