document.write( "Question 112307This question is from textbook
\n" ); document.write( ": Solve the system of equation. If the system is consistent, state the coordinates of the point of intersection. If not consistent, state whether it is inconsistent of dependent.\r
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\n" ); document.write( "2x+3y=11
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Algebra.Com's Answer #81926 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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( " \"1%2Ax-1%2Ay=3\"
\n" ); document.write( " \"2%2Ax%2B3%2Ay=11\"
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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( " \"-1%2Ay=3-1%2Ax\"Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%283-1%2Ax%29%2F-1\" Divide both sides by -1.
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\n" ); document.write( " Which breaks down and reduces to
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\n" ); document.write( " \"y=-3%2B1%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"-3%2B1%2Ax\" we can substitute the expression \"-3%2B1%2Ax\" into y of the 2nd equation. This will eliminate y so we can solve for x.
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\n" ); document.write( " \"2%2Ax%2B3%2Ahighlight%28%28-3%2B1%2Ax%29%29=11\" Replace y with \"-3%2B1%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"2%2Ax%2B3%2A%28-3%29%2B3%281%29x=11\" Distribute 3 to \"-3%2B1%2Ax\"
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\n" ); document.write( " \"2%2Ax-9%2B3%2Ax=11\" Multiply
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\n" ); document.write( " \"2%2Ax-9%2B3%2Ax=11\" Reduce any fractions
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\n" ); document.write( " \"2%2Ax%2B3%2Ax=11%2B9\"Add \"9\" to both sides
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\n" ); document.write( " \"2%2Ax%2B3%2Ax=20\" Combine the terms on the right side
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\n" ); document.write( " \"5%2Ax=20\" Now combine the terms on the left side.
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\n" ); document.write( " \"cross%28%281%2F5%29%285%2F1%29%29x=%2820%2F1%29%281%2F5%29\" Multiply both sides by \"1%2F5\". This will cancel out \"5%2F1\" and isolate x
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\n" ); document.write( " So when we multiply \"20%2F1\" and \"1%2F5\" (and simplify) we get
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\n" ); document.write( " \"x=4\" <---------------------------------One answer
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\n" ); document.write( " Now that we know that \"x=4\", lets substitute that in for x to solve for y
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\n" ); document.write( " \"2%284%29%2B3%2Ay=11\" Plug in \"x=4\" into the 2nd equation
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\n" ); document.write( " \"8%2B3%2Ay=11\" Multiply
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\n" ); document.write( " \"3%2Ay=11-8\"Subtract \"8\" from both sides
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\n" ); document.write( " \"3%2Ay=3\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F3%29%283%29%29%2Ay=%283%2F1%29%281%2F3%29\" Multiply both sides by \"1%2F3\". This will cancel out 3 on the left side.
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\n" ); document.write( " \"y=3%2F3\" Multiply the terms on the right side
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\n" ); document.write( " \"y=1\" Reduce
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\n" ); document.write( " So this is the other answer
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\n" ); document.write( " \"y=1\"<---------------------------------Other answer
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\n" ); document.write( " So our solution is
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\n" ); document.write( " \"x=4\" and \"y=1\"
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\n" ); document.write( " which can also look like
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\n" ); document.write( " (\"4\",\"1\")
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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-1%2Ay=3\"
\n" ); document.write( " \"2%2Ax%2B3%2Ay=11\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"1%2Ax-1%2Ay=3\" (red) and \"2%2Ax%2B3%2Ay=11\" (green) (hint: you may have to solve for y to graph these) intersecting at the blue circle.
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\n" ); document.write( " and we can see that the two equations intersect at (\"4\",\"1\"). This verifies our answer.
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\n" ); document.write( " Check:
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\n" ); document.write( " Plug in (\"4\",\"1\") into the system of equations
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\n" ); document.write( " Let \"x=4\" and \"y=1\". Now plug those values into the equation \"1%2Ax-1%2Ay=3\"
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\n" ); document.write( " \"1%2A%284%29-1%2A%281%29=3\" Plug in \"x=4\" and \"y=1\"
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\n" ); document.write( " \"4-1=3\" Multiply
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\n" ); document.write( " \"3=3\" Add
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\n" ); document.write( " \"3=3\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"4\",\"1\") satisfies \"1%2Ax-1%2Ay=3\"
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\n" ); document.write( " Let \"x=4\" and \"y=1\". Now plug those values into the equation \"2%2Ax%2B3%2Ay=11\"
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\n" ); document.write( " \"2%2A%284%29%2B3%2A%281%29=11\" Plug in \"x=4\" and \"y=1\"
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\n" ); document.write( " \"8%2B3=11\" Multiply
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\n" ); document.write( " \"11=11\" Add
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\n" ); document.write( " \"11=11\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"4\",\"1\") satisfies \"2%2Ax%2B3%2Ay=11\"
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\n" ); document.write( " Since the solution (\"4\",\"1\") satisfies the system of equations
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\n" ); document.write( " \"1%2Ax-1%2Ay=3\"
\n" ); document.write( " \"2%2Ax%2B3%2Ay=11\"
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\n" ); document.write( " this verifies our answer.
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