document.write( "Question 819987: Hi my name is Caroline,
\n" ); document.write( "I have a question on solving systems by substitution. How do I know whether to plug the first equation in for y or x? For example:
\n" ); document.write( "y= 2x +4
\n" ); document.write( "x=y-3\r
\n" ); document.write( "\n" ); document.write( "I know I have to plug in the 2x+4 into the second equation, I just don't know where! Any help would be appreciated!
\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #493333 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi,
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document.write( "y = 2x +4
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document.write( " x = y-3  ****
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document.write( " x = (2x+4) - 3    |Substituting  (2x+4)  for y
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document.write( " x = 2x + 1     |Solving for x
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document.write( " -1 = x   AND y  = 2    \"2%28-1%29%2B4%29\"
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document.write( "CHECKING our answer***
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document.write( " -1 = 2-3 = -1 \n" );
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