document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=131260>Question 131260</A>: <I><SPAN STYLE=\"word-break: break-all;\"> wihtout graphing, decide whether the points would lie on the graph of the equation.<BR>\n" );
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document.write( "    2x+4y=20\r<BR>\n" );
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document.write( "   a. (6,2)<BR>\n" );
document.write( "   b. (2,4)<BR>\n" );
document.write( "   c. (10,4) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #95820 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=95820\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The points you are given are in the form (x, y) ... the first number in the parentheses<BR>\n" );
document.write( "being the value of x and the number following the comma being the value in y. All you have<BR>\n" );
document.write( "to do for each of the given points is to substitute the x value for x in the equation and <BR>\n" );
document.write( "then also substitute the corresponding y value. If the equation still balances, then the <BR>\n" );
document.write( "point is on the graph.  So let's try this process for each of the three points.\r<BR>\n" );
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document.write( "First point is (6, 2) ... do x is 6 and y is 2. Substitute these two values for x and y in the<BR>\n" );
document.write( "given equation as follows:<BR>\n" );
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document.write( "2x + 4y = 20<BR>\n" );
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document.write( "2(6)+ 4(2) = 20<BR>\n" );
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document.write( "do the two multiplications on the left side to get<BR>\n" );
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document.write( "12 + 8 = 20<BR>\n" );
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document.write( "And since the left side of the equation equals the right side, the point (6, 2) is on the graph.<BR>\n" );
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document.write( "Now the second point ... (2, 4).  Substitute 2 for x and 4 for y:<BR>\n" );
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document.write( "2x + 4y = 20<BR>\n" );
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document.write( "2(2)+ 4(4) = 20<BR>\n" );
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document.write( "do the two multiplications on the left side to get<BR>\n" );
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document.write( "4 + 16 = 20<BR>\n" );
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document.write( "The left side of this equation equals the right side so the point (2, 4) is also on the graph.<BR>\n" );
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document.write( "Finally, the last point ... (10, 4) ....<BR>\n" );
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document.write( "2x + 4y = 20<BR>\n" );
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document.write( "2(10)+ 4(4) = 20<BR>\n" );
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document.write( "do the two multiplications on the left side to get<BR>\n" );
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document.write( "20 + 16 = 20<BR>\n" );
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document.write( "This time the left side does not equal the right side. Because of this you can say that the<BR>\n" );
document.write( "point (10, 4) is NOT on the graph.<BR>\n" );
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document.write( "Hope this helps you to understand the problem and how to answer it.<BR>\n" );
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document.write( ". </SPAN>\n" );
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