document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=137404>Question 137404</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072538953/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Tutor could you please assist and solve this by the substitution method?\r<BR>\n" );
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document.write( "3y = x + 5 <BR>\n" );
document.write( "3x - 9y = -10\r<BR>\n" );
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document.write( "I do so very much appreciate your help.<BR>\n" );
document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100535 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=100535\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3y = x + 5 ---------------------eq1<BR>\n" );
document.write( "3x - 9y = -10 -------------------eq2\r<BR>\n" );
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document.write( "We'll solve it three ways:\r<BR>\n" );
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document.write( "1.  From eq1, we see that x=3y-5 (we subtracted 5 from each side)<BR>\n" );
document.write( "Now substitute this into eq2 and we get:\r<BR>\n" );
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document.write( "3(3y-5)-9y=-10 or<BR>\n" );
document.write( "9y-15-9y=10-------------------------NO solution!!!\r<BR>\n" );
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document.write( "2.  Multiply eq1 by 3 and we get 9y=3x+15, substitute this into eq2\r<BR>\n" );
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document.write( "3x-(3x+15)=-10 or<BR>\n" );
document.write( "3x-3x-15=-10-------------------------NO solution!!!!!!\r<BR>\n" );
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document.write( "3. re-write eq2 as follows:\r<BR>\n" );
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document.write( "3x-3*(3y)=-10 now substitute 3y=x+5 into this:\r<BR>\n" );
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document.write( "3x-3(x+5)=-10<BR>\n" );
document.write( "3x-3x-15=-10--------------------------NO solution!!!!\r<BR>\n" );
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document.write( "The equations are inconsistent---they have no solution. Why?????\r<BR>\n" );
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document.write( "Write each equation in slope/intercept form(y=mx+b where m is the slope and b is the y-intercept)\r<BR>\n" );
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document.write( "eq1 3y=x+5 or (we divided both sides by 3)<BR>\n" );
document.write( "y=(1/3)x  +  5/3--------------------slope is 1/3\r<BR>\n" );
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document.write( "eq2  3x-9y=-10  subtract 3x from each side\r<BR>\n" );
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document.write( "-9y=-3x-10  multiply each side by -1<BR>\n" );
document.write( "9y=3x+10  divide each term by 9\r<BR>\n" );
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document.write( "y=(1/3)x+10/9---------------------------slope is 1/3\r<BR>\n" );
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document.write( "Both equations have a slope of 1/3 which means the lines are parallel\r<BR>\n" );
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document.write( "Hope this helps---ptaylor  </SPAN>\n" );
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