You can put this solution on YOUR website! Let = Luke's age
Let = Peter's age
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(1)
(2)
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Substitute (1) into (2)
(2)
(2)
(2)
and
(2)
(2)
(2)
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Luke is 24
Peter is 13
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check:
(1)
(1)
(1)
(1)
OK