document.write( "Question 596080: x+y=9 and y=2x \n" ); document.write( "
Algebra.Com's Answer #377499 by math-vortex(648)\"\" \"About 
You can put this solution on YOUR website!
Hi, there--
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\n" ); document.write( "We can use the the substitution method to solve this system.
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\n" ); document.write( "\"x%2By=9\"
\n" ); document.write( "\"y=2x\"
\n" ); document.write( ".
\n" ); document.write( "Since y is equal to 2x, we can substitute 2x for y in the first equation, and solve for x.
\n" ); document.write( "\"x%2By=9\"
\n" ); document.write( "\"x%2B2x=9\"
\n" ); document.write( "\"3x=9\"
\n" ); document.write( "\"x=3\"
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\n" ); document.write( "Now substitute 3 for x into either equation and solve for y. I'll use the second one.
\n" ); document.write( "\"y=2x\"
\n" ); document.write( "\"y=2%283%29\"
\n" ); document.write( "\"y=6\"
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\n" ); document.write( "According to our algebra the ordered pair (3,6) in the solution for this system.
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\n" ); document.write( "It's ALWAYS a good idea to check this solution in the original equations to make sure we did not make a mistake.
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\n" ); document.write( "CHECK:
\n" ); document.write( "\"x%2By=9\"
\n" ); document.write( "\"%283%29%2B%286%29=9\"
\n" ); document.write( "\"9=9\"
\n" ); document.write( "Perfect!
\n" ); document.write( ".
\n" ); document.write( "\"y=2x\"
\n" ); document.write( "\"%286%29=2%2A%283%29\"
\n" ); document.write( "\"6=6\"
\n" ); document.write( "Bingo!
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\n" ); document.write( "That's it! Feel free to email if you have questions about this.
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\n" ); document.write( "Ms.Figgy
\n" ); document.write( "math.in.the.vortex@gmail.com
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