SOLUTION: Write a system of equations that could be used to solve this problem: Joe is 28 years older than his daughter Mary. In 12 years he will be three times as old as Mary is now,.
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-> SOLUTION: Write a system of equations that could be used to solve this problem: Joe is 28 years older than his daughter Mary. In 12 years he will be three times as old as Mary is now,.
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Question 80939This question is from textbook Algebra Structure and Method
: Write a system of equations that could be used to solve this problem: Joe is 28 years older than his daughter Mary. In 12 years he will be three times as old as Mary is now,. This question is from textbook Algebra Structure and Method
You can put this solution on YOUR website! Let J = Joe's age now; Let M = Mary's age now
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Write an equation for each sentence:
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Joe is 28 years older than his daughter Mary.
J = M + 28
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In 12 years he will be three times as old as Mary is now,.
J + 12 = 3M
J = 3M - 12
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Using the 1st equation substitute (M+28) for J, find M
M + 28 = 3M - 12
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28 + 12 = 3M - M
:
40 = 2M
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M = 20 is Mary's age now
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We know J is 28 yrs older; Joe is 48 yr old now
