document.write( "Question 80939This question is from textbook Algebra Structure and Method
\n" ); document.write( ": 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,. \n" ); document.write( "
Algebra.Com's Answer #58075 by ankor@dixie-net.com(22740)\"\" \"About 
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Let J = Joe's age now; Let M = Mary's age now
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\n" ); document.write( "Write an equation for each sentence:
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\n" ); document.write( "Joe is 28 years older than his daughter Mary.
\n" ); document.write( "J = M + 28
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\n" ); document.write( "In 12 years he will be three times as old as Mary is now,.
\n" ); document.write( "J + 12 = 3M
\n" ); document.write( "J = 3M - 12
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\n" ); document.write( "Using the 1st equation substitute (M+28) for J, find M
\n" ); document.write( "M + 28 = 3M - 12
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\n" ); document.write( "28 + 12 = 3M - M
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\n" ); document.write( "40 = 2M
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\n" ); document.write( "M = 20 is Mary's age now
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\n" ); document.write( "We know J is 28 yrs older; Joe is 48 yr old now \n" ); document.write( "
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