document.write( "Question 841202: x+y=6 x+4y=3 using the substitution method.
\n" ); document.write( "2x-y=7 x+2y=1 using the addition method.
\n" ); document.write( "Thanks!
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Algebra.Com's Answer #506698 by mxgirl22(39)\"\" \"About 
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\n" ); document.write( "Problem #1.\r
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\n" ); document.write( "\n" ); document.write( "Solve using the substitution method.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=6\"
\n" ); document.write( "\"x%2B4y=3\"\r
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\n" ); document.write( "\n" ); document.write( "------------------------------------------------------------------------
\n" ); document.write( "1.) I'm going to label each equation in order to reference back to them.\r
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\n" ); document.write( "\n" ); document.write( "Equation 1.) \"x%2By=6\"\r
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\n" ); document.write( "\n" ); document.write( "Equation 2.) \"x%2B4y=3\"\r
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\n" ); document.write( "2.) Using equation #1 get \"x\" by itself.\r
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\n" ); document.write( "\n" ); document.write( "Equation 1.)\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=6\"
\n" ); document.write( "\"x%2By-y=6-y\"
\n" ); document.write( "\"x=6-y\"\r
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\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "3.) Now that you have \"x\" by itself, plug in \"x=6-y\" for equation 2. Solve for \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4y=3\"
\n" ); document.write( "\"%286-y%29%2B4y=3\"
\n" ); document.write( "\"6%2B3y=3\"
\n" ); document.write( "\"6-6%2B3y=3-6\"
\n" ); document.write( "\"3y=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"3y%2F3=-3%2F3\"
\n" ); document.write( "\"y=-1\"\r
\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "4.) Now that you solved for \"y\", plug in \"y=-1\" in to equation 1.
\n" ); document.write( "Solve for \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=6\"
\n" ); document.write( "\"x%2B%28-1%29=6\"
\n" ); document.write( "\"x-1=6\"
\n" ); document.write( "\"x-1%2B1=6%2B1\"
\n" ); document.write( "\"x=7\"\r
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\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "5.) Check \"x=7\" and \"y=-1\" for either equation 1 or equation 2.\r
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\n" ); document.write( "\n" ); document.write( "Equation 2.)\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4y=3\"
\n" ); document.write( "\"%287%29%2B4%28-1%29=3\"
\n" ); document.write( "\"7-4=3\"
\n" ); document.write( "\"3=3\"\r
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\n" ); document.write( "\n" ); document.write( "Checks!\r
\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "6.) Answer.\r
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\n" ); document.write( "\n" ); document.write( "\"x=7\" and \"y=-1\"\r
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\n" ); document.write( "\n" ); document.write( "for Problem #1\r
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\n" ); document.write( "Problem #2.\r
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\n" ); document.write( "\n" ); document.write( "Solve using the addition method.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=7\"
\n" ); document.write( "\"x%2B2y=1\"\r
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\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "1.) I'm going to label each equation in order to reference back to them.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Equation 1.) \"2x-y=7\" \r
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\n" ); document.write( "\n" ); document.write( "Equation 2.) \"x%2B2y=1\"\r
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\n" ); document.write( "\n" ); document.write( "---------------------------------
\n" ); document.write( "2.) Both look easy to manipulate, but, if we use equation 2 we will have smaller numbers.\r
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\n" ); document.write( "\n" ); document.write( "Equation 1.) \"2x-y=7\" \r
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\n" ); document.write( "\n" ); document.write( "Equation 2.) \"x%2B2y=1\"\r
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\n" ); document.write( "\n" ); document.write( "**First I'm going to get rid of the \"x\".\r
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\n" ); document.write( "\n" ); document.write( "Equation 2.) \r
\n" ); document.write( "\n" ); document.write( "\"x%2B2y=1\"
\n" ); document.write( "\"-2%28x%2B2y%29=-2%281%29\"
\n" ); document.write( "\"-2x-4y=-2\" <-----Your \"new\" equation. I'll name it equation 3.\r
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\n" ); document.write( "3.) Using equation 1 & equation 3 combine.\r
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\n" ); document.write( "\n" ); document.write( "Equation 1.) \"2x-y=7\"\r
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\n" ); document.write( "\n" ); document.write( "Equation 3.) \"-2x-4y=-2\"\r
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\n" ); document.write( "\n" ); document.write( "***Notice: \"2x\" will be gone.\r
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\n" ); document.write( "\n" ); document.write( "***** The \"y\" will now be -5y\r
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\n" ); document.write( "\n" ); document.write( "******* And \"7%2B%28-2%29=5\"\r
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\n" ); document.write( "\n" ); document.write( "******** The equation will now be \"-5y=5\" <---I'm calling this equation 4.\r
\n" ); document.write( "\n" ); document.write( "--------------------------------------------------
\n" ); document.write( "4.) Solve for \"y\" using equation 4.\r
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\n" ); document.write( "\n" ); document.write( "\"-5y=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"-5y%2F-5=5%2F-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1\"\r
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\n" ); document.write( "\n" ); document.write( "--------------------------------------------------
\n" ); document.write( "5.) Using either equation 1 or equation 2, plug in \"y=-1\" to solve for \"x\".\r
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\n" ); document.write( "\n" ); document.write( "Equation 1.) \r
\n" ); document.write( "\n" ); document.write( "\"2x-y=7\" \r
\n" ); document.write( "\n" ); document.write( "\"2x-%28-1%29=7\"\r
\n" ); document.write( "\n" ); document.write( "\"2x%2B1=7\"\r
\n" ); document.write( "\n" ); document.write( "\"2x%2B1-1=7-1\"\r
\n" ); document.write( "\n" ); document.write( "\"2x=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2F2=6%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "--------------------------------------------------
\n" ); document.write( "6.) Check \"x=3\" and \"y=-1\" for either equation 1 or equation 2.\r
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\n" ); document.write( "\n" ); document.write( "Equation 2.) \r
\n" ); document.write( "\n" ); document.write( "\"x%2B2y=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%283%29%2B2%28-1%29=1\"
\n" ); document.write( "\"3-2=1\"
\n" ); document.write( "\"1=1\"\r
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\n" ); document.write( "\n" ); document.write( "Checks!\r
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\n" ); document.write( "\n" ); document.write( "--------------------------------------------------
\n" ); document.write( "7.) Answer.\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\" and \"y=-1\"\r
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\n" ); document.write( "\n" ); document.write( "For Problem #2\r
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