document.write( "Question 82478: what does an answer \"no solution\" mean graphically? \n" ); document.write( "
Algebra.Com's Answer #59079 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Say we had the system of equations\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B5x=10\"
\n" ); document.write( "\"4x%2B10x=12\"\r
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\n" ); document.write( "\n" ); document.write( "Lets solve the system of equations\r
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Solved by pluggable solver: Solving a linear system of equations by subsitution

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\n" ); document.write( " Lets start with the given system of linear equations
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\n" ); document.write( " \"2%2Ax%2B5%2Ay=10\"
\n" ); document.write( " \"4%2Ax%2B10%2Ay=12\"
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\n" ); document.write( " Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to choose y.
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\n" ); document.write( " Solve for y for the first equation
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\n" ); document.write( " \"5%2Ay=10-2%2Ax\"Subtract \"2%2Ax\" from both sides
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\n" ); document.write( " \"y=%2810-2%2Ax%29%2F5\" Divide both sides by 5.
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\n" ); document.write( " Which breaks down and reduces to
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\n" ); document.write( " \"y=2-%282%2F5%29%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"2-%282%2F5%29%2Ax\" we can substitute the expression \"2-%282%2F5%29%2Ax\" into y of the 2nd equation. This will eliminate y so we can solve for x.
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\n" ); document.write( " \"4%2Ax%2B10%2Ahighlight%28%282-%282%2F5%29%2Ax%29%29=12\" Replace y with \"2-%282%2F5%29%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"4%2Ax%2B10%2A%282%29%2B10%28-2%2F5%29x=12\" Distribute 10 to \"2-%282%2F5%29%2Ax\"
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\n" ); document.write( " \"4%2Ax%2B20-%2820%2F5%29%2Ax=12\" Multiply
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\n" ); document.write( " \"4%2Ax%2B20-4%2Ax=12\" Reduce any fractions
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\n" ); document.write( " \"4%2Ax-4%2Ax=12-20\" Subtract \"20\" from both sides
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\n" ); document.write( " \"4%2Ax-4%2Ax=-8\" Combine the terms on the right side
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\n" ); document.write( " \"0%2Ax=-8\" Now combine the terms on the left side.
\n" ); document.write( " \"0%2F1=-8%2F1\" Since this expression is not true, we have an inconsistency.
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\n" ); document.write( " So there are no solutions. The simple reason is the 2 equations represent 2 parallel lines that will never intersect. Since no intersections occur, no solutions exist.
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\n" ); document.write( " graph of \"2%2Ax%2B5%2Ay=10\" (red) and \"4%2Ax%2B10%2Ay=12\" (green) (hint: you may have to solve for y to graph these)
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\n" ); document.write( " and we can see that the two equations are parallel and will never intersect. So this system is inconsistent
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