document.write( "Question 473343: Example: Find the point of intersection of the following lines.
\n" ); document.write( "x= 32 + y
\n" ); document.write( "3x= 8y+ 6
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Algebra.Com's Answer #324639 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"x=+32+%2B+y\"
\n" ); document.write( "\"3x=+8y%2B+6\"\r
\n" ); document.write( "\n" ); document.write( "write both of them in standard form \"Ax%5E2%2BBy=C\"\r
\n" ); document.write( "\n" ); document.write( "\"x-y=32\"
\n" ); document.write( "\"3x-8y=6\"\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( " \"1%2Ax-1%2Ay=32\"
\n" ); document.write( " \"3%2Ax-8%2Ay=6\"
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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=32-1%2Ax\"Subtract \"1%2Ax\" from both sides
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\n" ); document.write( " \"y=%2832-1%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=-32%2B1%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"-32%2B1%2Ax\" we can substitute the expression \"-32%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( " \"3%2Ax%2B-8%2Ahighlight%28%28-32%2B1%2Ax%29%29=6\" Replace y with \"-32%2B1%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"3%2Ax-8%2A%28-32%29-8%281%29x=6\" Distribute -8 to \"-32%2B1%2Ax\"
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\n" ); document.write( " \"3%2Ax%2B256-8%2Ax=6\" Multiply
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\n" ); document.write( " \"3%2Ax%2B256-8%2Ax=6\" Reduce any fractions
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\n" ); document.write( " \"3%2Ax-8%2Ax=6-256\" Subtract \"256\" from both sides
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\n" ); document.write( " \"3%2Ax-8%2Ax=-250\" Combine the terms on the right side
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\n" ); document.write( " \"-5%2Ax=-250\" Now combine the terms on the left side.
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\n" ); document.write( " \"cross%28%281%2F-5%29%28-5%2F1%29%29x=%28-250%2F1%29%281%2F-5%29\" Multiply both sides by \"1%2F-5\". This will cancel out \"-5%2F1\" and isolate x
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\n" ); document.write( " So when we multiply \"-250%2F1\" and \"1%2F-5\" (and simplify) we get
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\n" ); document.write( " \"x=50\" <---------------------------------One answer
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\n" ); document.write( " Now that we know that \"x=50\", lets substitute that in for x to solve for y
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\n" ); document.write( " \"3%2850%29-8%2Ay=6\" Plug in \"x=50\" into the 2nd equation
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\n" ); document.write( " \"150-8%2Ay=6\" Multiply
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\n" ); document.write( " \"-8%2Ay=6-150\"Subtract \"150\" from both sides
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\n" ); document.write( " \"-8%2Ay=-144\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F-8%29%28-8%29%29%2Ay=%28-144%2F1%29%281%2F-8%29\" Multiply both sides by \"1%2F-8\". This will cancel out -8 on the left side.
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\n" ); document.write( " \"y=-144%2F-8\" Multiply the terms on the right side
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\n" ); document.write( " \"y=18\" Reduce
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\n" ); document.write( " So this is the other answer
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\n" ); document.write( " \"y=18\"<---------------------------------Other answer
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\n" ); document.write( " So our solution is
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\n" ); document.write( " \"x=50\" and \"y=18\"
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\n" ); document.write( " which can also look like
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\n" ); document.write( " (\"50\",\"18\")
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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=32\"
\n" ); document.write( " \"3%2Ax-8%2Ay=6\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"1%2Ax-1%2Ay=32\" (red) and \"3%2Ax-8%2Ay=6\" (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 (\"50\",\"18\"). This verifies our answer.
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\n" ); document.write( " Plug in (\"50\",\"18\") into the system of equations
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\n" ); document.write( " Let \"x=50\" and \"y=18\". Now plug those values into the equation \"1%2Ax-1%2Ay=32\"
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\n" ); document.write( " \"1%2A%2850%29-1%2A%2818%29=32\" Plug in \"x=50\" and \"y=18\"
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\n" ); document.write( " \"50-18=32\" Multiply
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\n" ); document.write( " \"32=32\" Add
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\n" ); document.write( " \"32=32\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"50\",\"18\") satisfies \"1%2Ax-1%2Ay=32\"
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\n" ); document.write( " Let \"x=50\" and \"y=18\". Now plug those values into the equation \"3%2Ax-8%2Ay=6\"
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\n" ); document.write( " \"3%2A%2850%29-8%2A%2818%29=6\" Plug in \"x=50\" and \"y=18\"
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\n" ); document.write( " \"150-144=6\" Multiply
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\n" ); document.write( " \"6=6\" Add
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\n" ); document.write( " \"6=6\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"50\",\"18\") satisfies \"3%2Ax-8%2Ay=6\"
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\n" ); document.write( " Since the solution (\"50\",\"18\") satisfies the system of equations
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\n" ); document.write( " \"1%2Ax-1%2Ay=32\"
\n" ); document.write( " \"3%2Ax-8%2Ay=6\"
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\n" ); document.write( " this verifies our answer.
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