document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=177950>Question 177950</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618595538/algebrahomeworkh>McDougal Littell Algebra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> this question is about how to solve equation using substitution<BR>\n" );
document.write( "4x-7y=10<BR>\n" );
document.write( "y=x-7 <BR>\n" );
document.write( "what is x and y?\r<BR>\n" );
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document.write( "and question 10 ;<BR>\n" );
document.write( "2x-y=23<BR>\n" );
document.write( "x-9=-1<BR>\n" );
document.write( "what is x and y?\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #132917 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=132917\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I will do the first and you can do the 2nd<BR>\n" );
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document.write( "this is solving a system of equations. You are trying to find the value and values of x and y that will satisfy both equations. We are using the substitution method.  This means we will isolate a variable in one of the equations(x or y-makes no difference) and take the value of that variable and plug it into the other equation.\r<BR>\n" );
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document.write( "4x-7y=10....eq 1<BR>\n" );
document.write( "y=x-7.......eq 2 <BR>\n" );
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document.write( "In our particular situation y is already isolated in eq 2 and its value is x-7<BR>\n" );
document.write( "so we take that and plug that value into every place y occurs in eq 1 and solve for x<BR>\n" );
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document.write( "4x-7(x-7)=10.....plugged in y value of x-7(eq 1) <BR>\n" );
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document.write( "4x-7x+49=10.......distributed left side<BR>\n" );
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document.write( "-3x=-39......combined like terms on left and right<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=13%29 ALIGN=MIDDLE  ALT=\"highlight%28x=13%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "now we take x's found value and plug it back into either eq 1 or 2 and solve for y. I choose eq 2<BR>\n" );
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document.write( "y=x-7<BR>\n" );
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document.write( "y=13-7=6<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=6%29 ALIGN=MIDDLE  ALT=\"highlight%28y=6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "now if you take those values they should work as solution in both equations<BR>\n" );
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document.write( "4x-7y=10....eq 1---->4(13)-7(6)=10--->52-42=10--->10=10...check<BR>\n" );
document.write( "y=x-7.......eq 2---->6=13-7----------------------->6=6....check  </SPAN>\n" );
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