document.write( "Question 230125: please help me understand the difference between substitution and elimination method. use substitution to solve this system\r
\n" ); document.write( "\n" ); document.write( "3x-y=6
\n" ); document.write( "-4x+2y=-8 \n" ); document.write( "
Algebra.Com's Answer #170462 by algebrapro18(249)\"\" \"About 
You can put this solution on YOUR website!
Well your first question is what is the difference between elimination and substitution. Well for the substitution method you solve an equation for a particular variable and then substitute that equation into the other one and solve. With elimination you multiply an equation by a number and then add the two equations together and solve that way.
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\n" ); document.write( "\n" ); document.write( "So now to solve the system using substitution.
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\n" ); document.write( "\n" ); document.write( "3x-y=6
\n" ); document.write( "-4x+2y=-8
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\n" ); document.write( "\n" ); document.write( "Since equation 1 has y by its self lets solve it for y.
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\n" ); document.write( "\n" ); document.write( "3x-y=6
\n" ); document.write( "-y = -3x+6
\n" ); document.write( "y = 3x-6
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\n" ); document.write( "\n" ); document.write( "okay now plug that expression into the second equation and solve for x.
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\n" ); document.write( "\n" ); document.write( "-4x+2(3x-6)=-8
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\n" ); document.write( "\n" ); document.write( "I will leave you to solve that equation but you should get x=2.
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\n" ); document.write( "\n" ); document.write( "Now we plug our answer for x back into the expression and solve for y.
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\n" ); document.write( "\n" ); document.write( "y = 3x-6
\n" ); document.write( "y = 3(2)-6 = 0
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\n" ); document.write( "\n" ); document.write( "so the solution to your system is (2,0). \n" ); document.write( "
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