document.write( "Question 1154263: Twice my age plus three times my sister's age is 86. Three times my age plus four times my sister's age is 120. How old am I?
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Algebra.Com's Answer #776669 by ankor@dixie-net.com(22740)\"\" \"About 
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let m = my age
\n" ); document.write( "let s = sister's age
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\n" ); document.write( "Write an equation for each statement
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\n" ); document.write( " twice my age plus three times my sister's age is 86.
\n" ); document.write( "2m + 3s = 86
\n" ); document.write( " Three times my age plus four times my sister's age is 120.
\n" ); document.write( "3m + 4s = 120
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\n" ); document.write( "multiply the 1st equation by 3, the 2nd equation by 2
\n" ); document.write( "6m + 9s = 258
\n" ); document.write( "6m + 8s = 240
\n" ); document.write( "----------------subtraction eliminate m, find s
\n" ); document.write( "0 + s = 18 yr is sisters age
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\n" ); document.write( " How old am I?
\n" ); document.write( "2m + 3(18) = 86
\n" ); document.write( "2m + 54 = 86
\n" ); document.write( "2m = 86 - 54
\n" ); document.write( "2m = 32
\n" ); document.write( "m = 32/2
\n" ); document.write( "m = 16 yr is my age
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\n" ); document.write( "Check solutions in 2nd equation
\n" ); document.write( "3(16) + 4(18) =
\n" ); document.write( "48 + 72 = 120 \n" ); document.write( "
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