You can put this solution on YOUR website! Ja = Jack's present age
Ji = Jill's present age
:
Write an equation for each statement:
:
Jack is twice as old as Jill.
Ja = 2Ji
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In 2 years, Jack will be 4 times as old as Jill was 9 years ago.
Ja + 2 = 4(Ji - 9)
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Ja + 2 = 4Ji - 36
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Ja = 4Ji - 36 - 2
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Ja = 4Ji - 38
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Replace Ja with 2Ji, find Ji
2Ji = 4Ji - 38
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38 = 4Ji - 2Ji
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38 = 2Ji
Ji =
Ji = 19 yrs is Jill's present age
then
2(19) = 38 yrs is Jack's present age
:
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Check our solution in the statement
"In 2 years, Jack will be 4 times as old as Jill was 9 years ago."
38 + 2 = 4(19 - 9)
40 = 4(10)
