document.write( "Question 113863: My question pertains to solving linear equations using subsitution method.\r
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\n" ); document.write( "5x+2y = 0
\n" ); document.write( "x-3y = 0\r
\n" ); document.write( "\n" ); document.write( "Please show me detailed steps on doing a problem of this type - Thank you kindly!
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Algebra.Com's Answer #82882 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( " \"5%2Ax%2B2%2Ay=0\"
\n" ); document.write( " \"1%2Ax-3%2Ay=0\"
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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( " \"2%2Ay=0-5%2Ax\"Subtract \"5%2Ax\" from both sides
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\n" ); document.write( " \"y=%280-5%2Ax%29%2F2\" Divide both sides by 2.
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\n" ); document.write( " Which breaks down and reduces to
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\n" ); document.write( " \"y=0-%285%2F2%29%2Ax\" Now we've fully isolated y
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\n" ); document.write( " Since y equals \"0-%285%2F2%29%2Ax\" we can substitute the expression \"0-%285%2F2%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( " \"1%2Ax%2B-3%2Ahighlight%28%280-%285%2F2%29%2Ax%29%29=0\" Replace y with \"0-%285%2F2%29%2Ax\". Since this eliminates y, we can now solve for x.
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\n" ); document.write( " \"1%2Ax-3%2A%280%29-3%28-5%2F2%29x=0\" Distribute -3 to \"0-%285%2F2%29%2Ax\"
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\n" ); document.write( " \"1%2Ax%2B0%2B%2815%2F2%29%2Ax=0\" Multiply
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\n" ); document.write( " \"1%2Ax%2B0%2B%2815%2F2%29%2Ax=0\" Reduce any fractions
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\n" ); document.write( " \"1%2Ax%2B%2815%2F2%29%2Ax=0%2B0\"Add \"0\" to both sides
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\n" ); document.write( " \"1%2Ax%2B%2815%2F2%29%2Ax=0\" Combine the terms on the right side
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\n" ); document.write( " \"%282%2F2%29%2Ax%2B%2815%2F2%29x=0\" Make 1 into a fraction with a denominator of 2
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\n" ); document.write( " \"%2817%2F2%29%2Ax=0\" Now combine the terms on the left side.
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\n" ); document.write( " \"cross%28%282%2F17%29%2817%2F2%29%29x=%280%2F1%29%282%2F17%29\" Multiply both sides by \"2%2F17\". This will cancel out \"17%2F2\" and isolate x
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\n" ); document.write( " So when we multiply \"0%2F1\" and \"2%2F17\" (and simplify) we get
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\n" ); document.write( " \"x=0\" <---------------------------------One answer
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\n" ); document.write( " Now that we know that \"x=0\", lets substitute that in for x to solve for y
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\n" ); document.write( " \"1%280%29-3%2Ay=0\" Plug in \"x=0\" into the 2nd equation
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\n" ); document.write( " \"0-3%2Ay=0\" Multiply
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\n" ); document.write( " \"-3%2Ay=0%2B0\"Add \"0\" to both sides
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\n" ); document.write( " \"-3%2Ay=0\" Combine the terms on the right side
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\n" ); document.write( " \"cross%28%281%2F-3%29%28-3%29%29%2Ay=%280%2F1%29%281%2F-3%29\" Multiply both sides by \"1%2F-3\". This will cancel out -3 on the left side.
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\n" ); document.write( " \"y=0%2F-3\" Multiply the terms on the right side
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\n" ); document.write( " \"y=0\" Reduce
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\n" ); document.write( " So this is the other answer
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\n" ); document.write( " \"y=0\"<---------------------------------Other answer
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\n" ); document.write( " So our solution is
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\n" ); document.write( " \"x=0\" and \"y=0\"
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\n" ); document.write( " which can also look like
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\n" ); document.write( " (\"0\",\"0\")
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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%2B2%2Ay=0\"
\n" ); document.write( " \"1%2Ax-3%2Ay=0\"
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\n" ); document.write( " we get
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\n" ); document.write( " graph of \"5%2Ax%2B2%2Ay=0\" (red) and \"1%2Ax-3%2Ay=0\" (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 (\"0\",\"0\"). This verifies our answer.
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\n" ); document.write( " Check:
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\n" ); document.write( " Plug in (\"0\",\"0\") into the system of equations
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\n" ); document.write( " Let \"x=0\" and \"y=0\". Now plug those values into the equation \"5%2Ax%2B2%2Ay=0\"
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\n" ); document.write( " \"5%2A%280%29%2B2%2A%280%29=0\" Plug in \"x=0\" and \"y=0\"
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\n" ); document.write( " \"0%2B0=0\" Multiply
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\n" ); document.write( " \"0=0\" Add
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\n" ); document.write( " \"0=0\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"0\",\"0\") satisfies \"5%2Ax%2B2%2Ay=0\"
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\n" ); document.write( "
\n" ); document.write( " Let \"x=0\" and \"y=0\". Now plug those values into the equation \"1%2Ax-3%2Ay=0\"
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\n" ); document.write( " \"1%2A%280%29-3%2A%280%29=0\" Plug in \"x=0\" and \"y=0\"
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\n" ); document.write( "
\n" ); document.write( " \"0%2B0=0\" Multiply
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\n" ); document.write( "
\n" ); document.write( " \"0=0\" Add
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\n" ); document.write( "
\n" ); document.write( " \"0=0\" Reduce. Since this equation is true the solution works.
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\n" ); document.write( " So the solution (\"0\",\"0\") satisfies \"1%2Ax-3%2Ay=0\"
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\n" ); document.write( " Since the solution (\"0\",\"0\") satisfies the system of equations
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\n" ); document.write( " \"5%2Ax%2B2%2Ay=0\"
\n" ); document.write( " \"1%2Ax-3%2Ay=0\"
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\n" ); document.write( " this verifies our answer.
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