document.write( "Question 177973: Solve each system by the addition method. determine whether he equations are independent, dependent, or inconsistent.\r
\n" ); document.write( "\n" ); document.write( "x-y=3
\n" ); document.write( "-6x+6y=17\r
\n" ); document.write( "\n" ); document.write( "Thanks!!
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Algebra.Com's Answer #132939 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Solving a System of Linear Equations by Elimination/Addition

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\n" ); document.write( " Lets start with the given system of linear equations
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\n" ); document.write( " \"1%2Ax-1%2Ay=3\"
\n" ); document.write( " \"-6%2Ax%2B6%2Ay=17\"
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\n" ); document.write( " In order to solve for one variable, we must eliminate the other variable. So if we wanted to solve for y, we would have to eliminate x (or vice versa).
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\n" ); document.write( " So lets eliminate x. In order to do that, we need to have both x coefficients that are equal but have opposite signs (for instance 2 and -2 are equal but have opposite signs). This way they will add to zero.
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\n" ); document.write( " So to make the x coefficients equal but opposite, we need to multiply both x coefficients by some number to get them to an equal number. So if we wanted to get 1 and -6 to some equal number, we could try to get them to the LCM.
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\n" ); document.write( " Since the LCM of 1 and -6 is -6, we need to multiply both sides of the top equation by -6 and multiply both sides of the bottom equation by -1 like this:
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\n" ); document.write( " \"-6%2A%281%2Ax-1%2Ay%29=%283%29%2A-6\" Multiply the top equation (both sides) by -6
\n" ); document.write( " \"-1%2A%28-6%2Ax%2B6%2Ay%29=%2817%29%2A-1\" Multiply the bottom equation (both sides) by -1
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\n" ); document.write( " So after multiplying we get this:
\n" ); document.write( " \"-6%2Ax%2B6%2Ay=-18\"
\n" ); document.write( " \"6%2Ax-6%2Ay=-17\"
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\n" ); document.write( " Notice how -6 and 6 and -18 and -6 add to zero (ie \"-6%2B6=0\" \"6%2B-6=0\")
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\n" ); document.write( " However -18 and -17 add to -35 (ie \"-18%2B-17=-35\");
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\n" ); document.write( " So we're left with
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\n" ); document.write( " \"0=-35\"
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\n" ); document.write( " which means no value of x or y value will satisfy the system of equations. So there are no solutions
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\n" ); document.write( " So this system is inconsistent
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