document.write( "Question 949230: Plz help me with this..
\n" ); document.write( "Solve the following systems of equation using addition to eliminate one. If the system has no solution,indicate that it is inconsistent;if it has infininte solutions,indicate that it is Dependant;if the system has one solution,check your answer.
\n" ); document.write( "4x+2y=6
\n" ); document.write( "2x+y=3
\n" ); document.write( "Thank you
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Algebra.Com's Answer #579442 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"4x%2B2y=6\"
\n" ); document.write( "\"2x%2By=3\"
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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( " \"4%2Ax%2B2%2Ay=6\"
\n" ); document.write( " \"2%2Ax%2B1%2Ay=3\"
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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 4 and 2 to some equal number, we could try to get them to the LCM.
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\n" ); document.write( " Since the LCM of 4 and 2 is 4, we need to multiply both sides of the top equation by 1 and multiply both sides of the bottom equation by -2 like this:
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\n" ); document.write( " \"1%2A%284%2Ax%2B2%2Ay%29=%286%29%2A1\" Multiply the top equation (both sides) by 1
\n" ); document.write( " \"-2%2A%282%2Ax%2B1%2Ay%29=%283%29%2A-2\" Multiply the bottom equation (both sides) by -2
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\n" ); document.write( " So after multiplying we get this:
\n" ); document.write( " \"4%2Ax%2B2%2Ay=6\"
\n" ); document.write( " \"-4%2Ax-2%2Ay=-6\"
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\n" ); document.write( " Notice how 4 and -4 add to zero, 2 and -2 add to zero, 6 and -6 and to zero (ie \"4%2B-4=0\") \"2%2B-2=0\", and \"6%2B-6=0\")
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\n" ); document.write( " So we're left with
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\n" ); document.write( " \"0=0\"
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\n" ); document.write( " which means any x or y value will satisfy the system of equations. So there are an infinite number of solutions
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\n" ); document.write( " So this system is dependent
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