document.write( "Question 1100859: i'm older than my sister. 15 years ago her age was 1/3 of what my age is now. 10 years ago my age was twice what her age was 15 years ago. what is my age today? \n" ); document.write( "

Algebra.Com's Answer #715397 by josgarithmetic(39620) $\"\"$ $\"About$

You can put this solution on YOUR website!
y, \"my\" age
\n" ); document.write( "x, sister's age\r
\n" ); document.write( "\n" ); document.write( " $\"y%3Ex\"$
\n" ); document.write( "-
\n" ); document.write( " $\"system%28x-15=%281%2F3%29y%2Cy-10=2%28x-15%29%29\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"3x-45=y\"$
\n" ); document.write( "-
\n" ); document.write( " $\"%283x-45%29-10=2x-30\"$
\n" ); document.write( " $\"3x-55=2x-30\"$
\n" ); document.write( " $\"x=55-30\"$
\n" ); document.write( " $\"x=25\"$
\n" ); document.write( "-
\n" ); document.write( " $\"y=3x-45\"$
\n" ); document.write( " $\"y=75-45\"$
\n" ); document.write( " $\"highlight%28y=30%29\"$ \n" ); document.write( "

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