SOLUTION: John is 6 years older than his brother. The sum of their ages is 30. How old are John and his brother?

Question 925931: John is 6 years older than his brother. The sum of their ages is 30. How old are John and his brother?

Found 2 solutions by amariya, TimothyLamb:
Answer by amariya(8) (Show Source): You can put this solution on YOUR website!
john is 18,,,brother is 12======18+12=30
30-6=24,half of 24 is 12,,so 12,,,,then12+6=18
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
x = john age now
y = brother age now
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x = y + 6
x + y = 30
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put the system of linear equations into standard form
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x - y = 6
x + y = 30
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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 by matrix method:
x = john age now = 18
y = brother age now = 12
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by elimination:
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x - y = 6
x + y = 30
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add the two above equations:
2x = 36
x = 18
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18 + y = 30
y = 12
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solution by elimination method:
x = john age now = 18
y = brother age now = 12
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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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