SOLUTION: Seven years ago, my father's age was five times mine. Right now, his age is the sum of our two ages 7 years ago. How old am I? Thanks for your help.
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Question 924141: Seven years ago, my father's age was five times mine. Right now, his age is the sum of our two ages 7 years ago. How old am I? Thanks for your help. Answer by TimothyLamb(4379) (Show Source):
You can put this solution on YOUR website! x = father age now
y = son age now
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x - 7 = 5(y - 7)
x = (x - 7) + (y - 7)
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put the system of linear equations into standard form
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x - 7 = 5y - 35
x = x - 7 + y - 7
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x - 5y = - 28
y = 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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solution:
x = father age now = 42
y = son age now = 14
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now by substitution:
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x - 5y = - 28
y = 14
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x - 5*14 = - 28
x = 5*14 - 28
x = 42
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solution:
x = father age now = 42
y = son age now = 14
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