document.write( "Question 1130674: Use substitution to solve the system. (Simplify your answer completely. If the system is dependent, enter a general solution in terms of x and y. If there is no solution, enter NO SOLUTION.)\r
\n" ); document.write( "\n" ); document.write( "5x-2 / 4 + 1/2 = 3y+2 / 2\r
\n" ); document.write( "\n" ); document.write( "7y+3 / 3 = x/2 + 7/3
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Algebra.Com's Answer #747278 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"%285x-2+%29%2F+4+%2B+1%2F2+=+%283y%2B2%29+%2F+2+\"....both side multiply by \"4\"
\n" ); document.write( "\"%287y%2B3%29+%2F+3+=+x%2F2+%2B+7%2F3\"...both side multiply by \"3\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%285x-2+%29%2F+4+%2B+1%2A4%2F2+=+4%283y%2B2%29+%2F+2+\"
\n" ); document.write( "\"6%287y%2B3%29+%2F+3+=+6x%2F2+%2B+%286%2A7%29%2F3\"
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\n" ); document.write( "\n" ); document.write( "\"5x-2++%2B+2+=+2%283y%2B2%29++\"
\n" ); document.write( "\"2%287y%2B3%29++=+3x+%2B+2%2A7\"
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\n" ); document.write( "\n" ); document.write( "\"5x=+6y%2B4++\"
\n" ); document.write( "\"14y%2B6++=+3x+%2B+14\"
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\n" ); document.write( "\n" ); document.write( "\"5x-6y=4++\"
\n" ); document.write( "\"-3x%2B14y=++8\"\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( " \"5%2Ax-6%2Ay=4\"
\n" ); document.write( " \"-3%2Ax%2B14%2Ay=8\"
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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( " \"-6%2Ay=4-5%2Ax\"Subtract \"5%2Ax\" from both sides
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\n" ); document.write( " \"y=%284-5%2Ax%29%2F-6\" Divide both sides by -6.
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\n" ); document.write( " Which breaks down and reduces to
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\n" ); document.write( " \"y=-2%2F3%2B%285%2F6%29%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"-2%2F3%2B%285%2F6%29%2Ax\" we can substitute the expression \"-2%2F3%2B%285%2F6%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( " \"-3%2Ax%2B14%2Ahighlight%28%28-2%2F3%2B%285%2F6%29%2Ax%29%29=8\" Replace y with \"-2%2F3%2B%285%2F6%29%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"-3%2Ax%2B14%2A%28-2%2F3%29%2B14%285%2F6%29x=8\" Distribute 14 to \"-2%2F3%2B%285%2F6%29%2Ax\"
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\n" ); document.write( " \"-3%2Ax-28%2F3%2B%2870%2F6%29%2Ax=8\" Multiply
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\n" ); document.write( " \"-3%2Ax-28%2F3%2B%2835%2F3%29%2Ax=8\" Reduce any fractions
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\n" ); document.write( " \"-3%2Ax%2B%2835%2F3%29%2Ax=8%2B28%2F3\"Add \"28%2F3\" to both sides
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\n" ); document.write( " \"-3%2Ax%2B%2835%2F3%29%2Ax=24%2F3%2B28%2F3\" Make 8 into a fraction with a denominator of 3
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\n" ); document.write( " \"-3%2Ax%2B%2835%2F3%29%2Ax=52%2F3\" Combine the terms on the right side
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\n" ); document.write( " \"%28-9%2F3%29%2Ax%2B%2835%2F3%29x=52%2F3\" Make -3 into a fraction with a denominator of 3
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\n" ); document.write( " \"%2826%2F3%29%2Ax=52%2F3\" Now combine the terms on the left side.
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\n" ); document.write( " \"cross%28%283%2F26%29%2826%2F3%29%29x=%2852%2F3%29%283%2F26%29\" Multiply both sides by \"3%2F26\". This will cancel out \"26%2F3\" and isolate x
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\n" ); document.write( " So when we multiply \"52%2F3\" and \"3%2F26\" (and simplify) we get
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\n" ); document.write( " \"x=2\" <---------------------------------One answer
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\n" ); document.write( " Now that we know that \"x=2\", lets substitute that in for x to solve for y
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\n" ); document.write( " \"-3%282%29%2B14%2Ay=8\" Plug in \"x=2\" into the 2nd equation
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\n" ); document.write( " \"-6%2B14%2Ay=8\" Multiply
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\n" ); document.write( " \"14%2Ay=8%2B6\"Add \"6\" to both sides
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\n" ); document.write( " \"14%2Ay=14\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F14%29%2814%29%29%2Ay=%2814%2F1%29%281%2F14%29\" Multiply both sides by \"1%2F14\". This will cancel out 14 on the left side.
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\n" ); document.write( " \"y=14%2F14\" 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=2\" and \"y=1\"
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\n" ); document.write( " which can also look like
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\n" ); document.write( " (\"2\",\"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( " \"5%2Ax-6%2Ay=4\"
\n" ); document.write( " \"-3%2Ax%2B14%2Ay=8\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"5%2Ax-6%2Ay=4\" (red) and \"-3%2Ax%2B14%2Ay=8\" (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 (\"2\",\"1\"). This verifies our answer.
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\n" ); document.write( " Plug in (\"2\",\"1\") into the system of equations
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\n" ); document.write( " Let \"x=2\" and \"y=1\". Now plug those values into the equation \"5%2Ax-6%2Ay=4\"
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\n" ); document.write( " \"5%2A%282%29-6%2A%281%29=4\" Plug in \"x=2\" and \"y=1\"
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\n" ); document.write( " \"10-6=4\" Multiply
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\n" ); document.write( " \"4=4\" Add
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\n" ); document.write( " \"4=4\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"2\",\"1\") satisfies \"5%2Ax-6%2Ay=4\"
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\n" ); document.write( " Let \"x=2\" and \"y=1\". Now plug those values into the equation \"-3%2Ax%2B14%2Ay=8\"
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\n" ); document.write( " \"-3%2A%282%29%2B14%2A%281%29=8\" Plug in \"x=2\" and \"y=1\"
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\n" ); document.write( " \"-6%2B14=8\" Multiply
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\n" ); document.write( " \"8=8\" Add
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\n" ); document.write( " \"8=8\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"2\",\"1\") satisfies \"-3%2Ax%2B14%2Ay=8\"
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\n" ); document.write( " Since the solution (\"2\",\"1\") satisfies the system of equations
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\n" ); document.write( " \"5%2Ax-6%2Ay=4\"
\n" ); document.write( " \"-3%2Ax%2B14%2Ay=8\"
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\n" ); document.write( " this verifies our answer.
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