document.write( "Question 697634: the sum of the age of mother and her daughter is 70 years. 10 years ago,three times the age of mother was the same as seven times the age of her daughter. find the mother's present age? \n" ); document.write( "
Algebra.Com's Answer #430230 by ankor@dixie-net.com(22740)\"\" \"About 
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Write an equation for each statement
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\n" ); document.write( "\"the sum of the age of mother and her daughter is 70 years.\"
\n" ); document.write( "m + d = 70:
\n" ); document.write( "d = (70-m)
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\n" ); document.write( "\" 10 years ago,three times the age of mother was the same as seven times the age of her daughter.
\n" ); document.write( "3(m-10) = 7(d-10)
\n" ); document.write( "3m - 30 = 7d - 70
\n" ); document.write( "3m = 7d - 70 + 30
\n" ); document.write( "3m = 7d - 40
\n" ); document.write( "Replace d with (70-m)
\n" ); document.write( "3m = 7(70-m) - 40
\n" ); document.write( "3m = 490 - 7m - 40
\n" ); document.write( "3m + 7m = 490 - 40
\n" ); document.write( "10m = 450
\n" ); document.write( "m = 45 is Mom's age
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\n" ); document.write( "You can find d's age and confirm this solution in the last statement\r
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