SOLUTION: Jack is 3 times as old as Lacy. 4 years ago the sum of their ages was 12. How old are they now?

Question 926396: Jack is 3 times as old as Lacy. 4 years ago the sum of their ages was 12. How old are they now?
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
x = jack age now
y = lacy age now
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x = 3y
(x - 4) + (y - 4) = 12
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put the system of linear equations into standard form
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x - 3y = 0
x + y - 8 = 12
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x - 3y = 0
x + y = 20
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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 = jack age now = 15
y = lacy age now = 5
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Solve and graph linear equations:
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Solve quadratic equations, quadratic formula:
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Solve systems of linear equations up to 6-equations 6-variables:
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