document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=996236>Question 996236</A>: <I><SPAN STYLE=\"word-break: break-all;\"> \"Write an equation for each line\", and I picked two points from each line.\r<BR>\n" );
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document.write( "#1 The first line: (0, 3) & (-4, 0)<BR>\n" );
document.write( "Options:\r<BR>\n" );
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document.write( "A) y = (3/4)x + 3<BR>\n" );
document.write( "B) y = (4/3)x + 3<BR>\n" );
document.write( "C) y = (-4/3)x + 3<BR>\n" );
document.write( "D) y = (-3/4)x + 3\r<BR>\n" );
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document.write( "#2 The second line: (-2, 2) & (2, -3)<BR>\n" );
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document.write( "A) y = (-3/2)x + 1/2<BR>\n" );
document.write( "B) y = (3/2)x - 1/2<BR>\n" );
document.write( "C) y = (3/2)x + 1/2<BR>\n" );
document.write( "D) y = (-3/2)x - 1/2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #614751 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=614751\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> slope intercept form of the equation of a straight line is y = mx + b<BR>\n" );
document.write( "m is the slope.<BR>\n" );
document.write( "b is the y-intercept.\r<BR>\n" );
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document.write( "given two points (x1,y1) and (x2,y1), the slope is equal to (y2-y1) / (x2-x1).\r<BR>\n" );
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document.write( "once you know the slope, you can use one of the points to find the y-intercept.<BR>\n" );
document.write( "either one will do.<BR>\n" );
document.write( "both will give you the same answer.\r<BR>\n" );
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document.write( "since the y-intercept is the value of y when x = 0, if one of the points is already at x = 0, then you already have your y-intercept.\r<BR>\n" );
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document.write( "#1 The first line: (0, 3) & (-4, 0)\r<BR>\n" );
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document.write( "slope = (y2-y1) / (x2-x1)\r<BR>\n" );
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document.write( "y2 = 0<BR>\n" );
document.write( "y1 = 3<BR>\n" );
document.write( "x2 = -4<BR>\n" );
document.write( "x1 = 0\r<BR>\n" );
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document.write( "slope = (0-3) / (-4-0) = -3/-4 = 3/4\r<BR>\n" );
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document.write( "y-intercept = (0,3)\r<BR>\n" );
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document.write( "y = mx + b becomes y = 3/4*x + 3\r<BR>\n" );
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document.write( "Options:\r<BR>\n" );
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document.write( "A) y = (3/4)x + 3<BR>\n" );
document.write( "B) y = (4/3)x + 3<BR>\n" );
document.write( "C) y = (-4/3)x + 3<BR>\n" );
document.write( "D) y = (-3/4)x + 3\r<BR>\n" );
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document.write( "selection A is your answer.\r<BR>\n" );
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document.write( "the graph of your equation is shown below:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2015/101301.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( "#2 The second line: (-2, 2) & (2, -3)\r<BR>\n" );
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document.write( "y2 = -3<BR>\n" );
document.write( "y1 = 2<BR>\n" );
document.write( "x2 = 2<BR>\n" );
document.write( "x1 = -2\r<BR>\n" );
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document.write( "slope = (-3-2) / (2-(-2)) = -5/4\r<BR>\n" );
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document.write( "y = mx + b becomes y = -5/4*x + b, where b is the y-intercept.\r<BR>\n" );
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document.write( "use x1,y1 as a point.<BR>\n" );
document.write( "x1,y1 = (-2,2)<BR>\n" );
document.write( "replace y with 2 and replace x with -2 to get:<BR>\n" );
document.write( "y = -5/4*x + b becomes 2 = -5/4*(-2) + b<BR>\n" );
document.write( "simplify to get 2 = 10/4 + b<BR>\n" );
document.write( "subtract 10/4 from both sides of the equation to get b = 2 - 10/4 = 8/4 - 10/4 = -2/4\r<BR>\n" );
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document.write( "y = mx + b becomes:\r<BR>\n" );
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document.write( "y = -5/4*x - 1/2\r<BR>\n" );
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document.write( "Options:\r<BR>\n" );
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document.write( "A) y = (-3/2)x + 1/2<BR>\n" );
document.write( "B) y = (3/2)x - 1/2<BR>\n" );
document.write( "C) y = (3/2)x + 1/2<BR>\n" );
document.write( "D) y = (-3/2)x - 1/2 \r<BR>\n" );
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document.write( "none of the selections are the answer because the slope is -5/4 and not any combination of 3/2.\r<BR>\n" );
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document.write( "i was able to get the line correct and the points you referenced are on that line so i believe my answer is correct even though none of your selections match it.\r<BR>\n" );
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document.write( "here's a graph of my equation for your second problem.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2015/101302.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( "i took the extra step to graph all of your the selections for the second problem.\r<BR>\n" );
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document.write( "none of them passed through the required points.\r<BR>\n" );
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document.write( "check your second problem to make sure you copied it correctly.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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