document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1205724>Question 1205724</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system by the substitution method. If there is exactly one solution, write as an ordered pair. If not, choose one of the other options.\r<BR>\n" );
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document.write( "{(7x,-,7y,=,-28),(6x,+,y,=,-10):}\r<BR>\n" );
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document.write( "A. One solution:\r<BR>\n" );
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document.write( "B. No solution\r<BR>\n" );
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document.write( "C. Infinite number of solutions </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #842720 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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/cgi-bin/show-face.mpl?user=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=842720\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Solve the system by the substitution method. If there is exactly one solution, <BR>\n" );
document.write( "write as an ordered pair. If not, choose one of the other options.<BR>\n" );
document.write( "7x - 7y = -28,<BR>\n" );
document.write( "6x +  y = -10.<BR>\n" );
document.write( "A. One solution:<BR>\n" );
document.write( "B. No solution<BR>\n" );
document.write( "C. Infinite number of solutions<BR>\n" );
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document.write( "From second equation, express y = -10-6x.\r\n" );
document.write( "Now substitute this expression into first equation.  You will get\r\n" );
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document.write( "    7x - 7*(-10-6x) = -28\r\n" );
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document.write( "You have now one equation with one unknown x.\r\n" );
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document.write( "Simplify this equation and find x from it\r\n" );
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document.write( "    7x + 70 + 42x = -28\r\n" );
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document.write( "    7x + 42x = -28 - 70\r\n" );
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document.write( "      49x    =   -98\r\n" );
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document.write( "        x    =   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-98%29%2F49 ALIGN=MIDDLE  ALT=\"%28-98%29%2F49\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -2.\r\n" );
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document.write( "Thus you just found out one unknown  x= -2.\r\n" );
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document.write( "To find y, use this expression  y = -10-6x = -10 - 6*(-2) = -10 + 12 = 2.\r\n" );
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document.write( "<U>ANSWER</U>.  The system has one and only one solution x= -2,  y= 2.\r\n" );
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document.write( "To check your solution, substitute these found values into equations\r\n" );
document.write( "and make sure that in each equation the number in the left side is the same as in the right side.\r\n" );
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document.write( "Solved, with all necessary explanations.\r<BR>\n" );
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document.write( "From my post, learn how to write your problem, when you post it to this forum.\r<BR>\n" );
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document.write( "Do not use so many commas: they are unnecessary, so take them out.\r<BR>\n" );
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document.write( "Simply write each equation in separate line and do not use commas.<BR>\n" );
document.write( "Also, do not use curved brackets: they also are unnecessary.\r<BR>\n" );
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document.write( "Happy learning (!)\r<BR>\n" );
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document.write( "Come again to this forum soon to learn something new.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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