document.write( "Question 1210619: Fill in the blanks so that the resulting system does not have a unique solution.\r
\n" ); document.write( "\n" ); document.write( "8x + 12y = 26\r
\n" ); document.write( "\n" ); document.write( "8x + 12y = 1\r
\n" ); document.write( "\n" ); document.write( "14x + 16y = 14\r
\n" ); document.write( "\n" ); document.write( "14x + 16y = -8\r
\n" ); document.write( "\n" ); document.write( "20x + 35y = 19\r
\n" ); document.write( "\n" ); document.write( "20x + 35y = 4
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Algebra.Com's Answer #854432 by KMST(5360)\"\" \"About 
You can put this solution on YOUR website!
I see no blanks. I only see 6 linear equations on 2 variables.
\n" ); document.write( "It is not a properly defined question, but I will answer it for educational purposes, making some assumptions.
\n" ); document.write( "I am assuming that the answer expected is a system of 2 equations made using the equations listed.
\n" ); document.write( "We can make 15 different systems of 2 equations with the equations listed.
\n" ); document.write( "A system of 2 equations on 2 variables could have either a unique solution, or no solution, or infinite solutions.
\n" ); document.write( "In this case, I will show below that we cannot form a system of equations with infinite solutions from the equation listed.
\n" ); document.write( "The only systems of 2 equations with no unique solution that we can form the equations listed are systems with no solution.
\n" ); document.write( "From the equations listed, we could form a system of 3 equations with no solution by taking any 3 of the equations listed,
\n" ); document.write( "but I do not think that is the answer expected.
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\n" ); document.write( "The graph of a linear equation on the x-y coordinate plane is a straight line.
\n" ); document.write( "Two lines on a plane could
\n" ); document.write( "be parallel, having no points in common, or
\n" ); document.write( "intersect at only one point.
\n" ); document.write( "If the graphs of two linear equations have 2 points in common,
\n" ); document.write( "then both equations represent the same line, such as \"2x%2B3y=5\" and \"4x%2B6y=10\".
\n" ); document.write( "A system of two linear equations whose graph shows two intersecting straight line has one solution:
\n" ); document.write( "the coordinates of the intersection point, the only ordered pair (x,y) that satisfies both equations.\r
\n" ); document.write( "\n" ); document.write( "On a coordinate plane, each of the equations listed would represent a straight line, as shown below.
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\n" ); document.write( "There are 6 lines visible in the graph, and some visible intersection points,
\n" ); document.write( "representing unique solutions for some of the possible systems of 2 linear equations.
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\n" ); document.write( "SYSTEMS WITH UNIQUE SOLUTIONS:
\n" ); document.write( "The graph for a system of 2 equations on 2 variables with a unique solution shows 2 lines intersecting at just one point.
\n" ); document.write( "The coordinates of the intersection point are the unique solution.
\n" ); document.write( "Those systems are not the answer we are looking for.
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\n" ); document.write( "SYSTEMS WITH INFINITE SOLUTIONS:
\n" ); document.write( "A system with infinite solutions does not have a unique solution, and could be a valid answer.
\n" ); document.write( "The graph for a system of 2 equations on 2 variables with infinite solutions would show one line because the two equations represent the same line.
\n" ); document.write( "That would be the case when you can obtain one of the equations by multiplying the other one by some number other than zero, as in \"system%282x%2B3y=5%2C4x%2B6y=10%29\" .
\n" ); document.write( "A system like that cannot be made from the equations listed.
\n" ); document.write( "The only way to turn the left hand side of one equations into the left hand side of another is using the first 2,
\n" ); document.write( "or the third and fourth equations, or fifth and fourth equations, and multiply by 1,
\n" ); document.write( "but we would get the same equation and we see no repeats in the list of equations.
\n" ); document.write( "We cannot do it with equations that have different left hand sides, because the ratios of the x and y coefficients are different.
\n" ); document.write( "\"8%2F12=3%2F4\" for the first two,
\n" ); document.write( "\"14%2F16=7%2F8\" for the third and fourth equations, and
\n" ); document.write( "\"20%2F35=4%2F7\" for third and fourth equations.
\n" ); document.write( "We cannot turn one of the left hand sides \"8x%2B12y\" , \"14x%2B+16y\" and \"20x%2B35y\" into another by multiplying by any number except zero.
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\n" ); document.write( "So a systems with no unique solution that we can form from the list of \r
\n" ); document.write( "\n" ); document.write( "SYTEMS WITH NO SOLUTION:
\n" ); document.write( "The graph for a system of 2 equations on 2 variables with no solution shows 2 parallel lines.
\n" ); document.write( "There is no point on the x-y coordinate plane that satisfies both equations.
\n" ); document.write( "That is obvious for the system \"highlight%28system%288x%2B12y=26%2C8x%2B12y=1%29%29\" formed by the first 2 equations,
\n" ); document.write( "because the value of the linear function on 2 variables \"f%28x%2Cy%29=8x%2B12y\" cannot be 26 and 1 for the same ordered pair (x,y).
\n" ); document.write( "The slope of the lines represented by \"8x%2B12y=26\"<->\"y=%28-4%2F3%29%2B13%2F4\" and \"8x%2B12y=1\"<->\"y=%28-4%2F3%29%2B1%2F4+is+%7B%7B%7B-3%2F4\" .
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\n" ); document.write( "Another system with no solution can be formed by the third and fourth equations; \"highlight%28system%2814x+%2B+16y+=+14%2C%0D%0A14x+%2B+16y+=+-8%29%29\" .
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\n" ); document.write( "The same can be said of the system formed by the fifth and sixth equations:\"highlight%28system%28%0D%0A20x+%2B+35y+=+19%2C%0D%0A20x+%2B+35y+=+4%29%29\" .
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