document.write( "Question 593127: In 10 years, A will be twice as old as B was 10 years ago. If A is now 9 years older than B, the present age of B is \n" ); document.write( "

Algebra.Com's Answer #376198 by mathhelp@(10) $\"\"$ $\"About$

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Problem:\r
\n" ); document.write( "\n" ); document.write( "In 10 years, A will be twice as old as B was 10 years ago. If A is now 9 years older than B, the present age of B is\r
\n" ); document.write( "\n" ); document.write( "lets use A=x
\n" ); document.write( "B=y\r
\n" ); document.write( "\n" ); document.write( "Now: x = y+9
\n" ); document.write( "In ten years: x = 2y-10 = x+10=2y\r
\n" ); document.write( "\n" ); document.write( "lets solve!\r
\n" ); document.write( "\n" ); document.write( "x = 2y-10
\n" ); document.write( "x = y+9 \r
\n" ); document.write( "\n" ); document.write( "ok, so you have to make one of the equations cancel out x or y\r
\n" ); document.write( "\n" ); document.write( "lets cancel out x by multiplying everything by the negative sign (-)\r
\n" ); document.write( "\n" ); document.write( "x = 2y-10
\n" ); document.write( "-x = -y-9
\n" ); document.write( "-----------
\n" ); document.write( "0 = y-19\r
\n" ); document.write( "\n" ); document.write( "so y is 19\r
\n" ); document.write( "\n" ); document.write( "lets find x\r
\n" ); document.write( "\n" ); document.write( "2(19)-10 = x\r
\n" ); document.write( "\n" ); document.write( "x is 38-10, which is 28 \n" ); document.write( "

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