document.write( "Question 1008528: solving sytems of equations using elimination and my promblem
\n" ); document.write( "is x+y=4.4
\n" ); document.write( " 2x+y=3.8
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Algebra.Com's Answer #624169 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
\"x%2By=4.4\"
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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%2B1%2Ay=4.4\"
\n" ); document.write( " \"2%2Ax%2B1%2Ay=3.8\"
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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 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 1 and 2 is 2, we need to multiply both sides of the top equation by 2 and multiply both sides of the bottom equation by -1 like this:
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\n" ); document.write( " \"2%2A%281%2Ax%2B1%2Ay%29=%284.4%29%2A2\" Multiply the top equation (both sides) by 2
\n" ); document.write( " \"-1%2A%282%2Ax%2B1%2Ay%29=%283.8%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( " \"2%2Ax%2B2%2Ay=8.8\"
\n" ); document.write( " \"-2%2Ax-1%2Ay=-3.8\"
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\n" ); document.write( " Notice how 2 and -2 add to zero (ie \"2%2B-2=0\")
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\n" ); document.write( " Now add the equations together. In order to add 2 equations, group like terms and combine them
\n" ); document.write( " \"%282%2Ax-2%2Ax%29%2B%282%2Ay-1%2Ay%29=8.8-3.8\"
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\n" ); document.write( " \"%282-2%29%2Ax%2B%282-1%29y=8.8-3.8\"
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\n" ); document.write( " \"cross%282%2B-2%29%2Ax%2B%282-1%29%2Ay=8.8-3.8\" Notice the x coefficients add to zero and cancel out. This means we've eliminated x altogether.
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\n" ); document.write( " So after adding and canceling out the x terms we're left with:
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\n" ); document.write( " \"1%2Ay=5\"
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\n" ); document.write( " \"y=5\" Divide both sides by \"1\" to solve for y
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\n" ); document.write( " \"y=5\" Reduce
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\n" ); document.write( " Now plug this answer into the top equation \"1%2Ax%2B1%2Ay=4.4\" to solve for x
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\n" ); document.write( " \"1%2Ax%2B1%285%29=4.4\" Plug in \"y=5\"
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\n" ); document.write( " \"1%2Ax%2B5=4.4\" Multiply
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\n" ); document.write( " \"1%2Ax=4.4-5\" Subtract \"5\" from both sides
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\n" ); document.write( " \"1%2Ax=-0.600000000000001\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F1%29%281%29%29%2Ax=%28-0.600000000000001%29%281%2F1%29\" Multiply both sides by \"1%2F1\". This will cancel out \"1\" on the left side.
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\n" ); document.write( " \"x=-0.600000000000001\" Multiply the terms on the right side
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\n" ); document.write( " So our answer is
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\n" ); document.write( " \"x=-0.600000000000001\", \"y=5\"
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\n" ); document.write( " which also looks like
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\n" ); document.write( " (\"-0.600000000000001\", \"5\")
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\n" ); document.write( " Notice if we graph the equations (if you need help with graphing, check out this solver)
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\n" ); document.write( " \"1%2Ax%2B1%2Ay=4.4\"
\n" ); document.write( " \"2%2Ax%2B1%2Ay=3.8\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"1%2Ax%2B1%2Ay=4.4\" (red) \"2%2Ax%2B1%2Ay=3.8\" (green) (hint: you may have to solve for y to graph these) and the intersection of the lines (blue circle).
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\n" ); document.write( " and we can see that the two equations intersect at (\"-0.600000000000001\",\"5\"). This verifies our answer.

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\n" ); document.write( "\n" ); document.write( "you can also round it to \"x=-0.6+\"\r
\n" ); document.write( "\n" ); document.write( "so, solutions are: \r
\n" ); document.write( "\n" ); document.write( "\"x=-0.6+\"
\n" ); document.write( "\"y=5\"
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