Question 924144: [Demola is 2 years older than john, peter is half of demola's age, the sum of their ages is 23. How old is john?] Found 2 solutions by TimothyLamb, MathTherapy:Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website! x = demo age now
y = john age now
z = pete age now
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x = y + 2
z = (1/2)x
x + y + z = 23
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put the system of linear equations into standard form
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x - y = 2
0.5x - z = 0
x + y + z = 23
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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 = demo age now = 10
y = john age now = 8
z = pete age now = 5
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Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php Answer by MathTherapy(10552) (Show Source): You can put this solution on YOUR website!
[Demola is 2 years older than john, peter is half of demola's age, the sum of their ages is 23. How old is john?]
Let Demola's current age, be D
Then John's is: D - 2
Peter's is: , or
As their ages sum to 23, we get:
4D + D = 50 ------- Multiplying by LCD, 2
5D = 50
D, or Demola's current age = , or
John's current age: 10 - 2, or
Peter's current age: , or