document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=249498>Question 249498</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write th slope intercept form of an equation of the line that passes through the point (4,4) and has the slope m=5. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #181709 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=181709\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Slope-intercept form is:  y = mx+b<BR>\n" );
document.write( "m = 5 (given)<BR>\n" );
document.write( "Since the slope = rise/run = change in 'y' divided by change in 'x', m=5 tells us that for a change of 1 in x we have a change of 5 in y.<BR>\n" );
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document.write( "One point is given:  (4,4)<BR>\n" );
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document.write( "Substituting back into the equation, we have...<BR>\n" );
document.write( "4 = 5(4) + b<BR>\n" );
document.write( "4 = 20 + b<BR>\n" );
document.write( "-16 = b<BR>\n" );
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document.write( "So the intercept appears to be -16.<BR>\n" );
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document.write( "The resulting equation is:<BR>\n" );
document.write( "y = 5x - 16<BR>\n" );
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document.write( "Is it true for (4,4)?<BR>\n" );
document.write( "Yes.<BR>\n" );
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document.write( "Is it true for another point?<BR>\n" );
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document.write( "Well, we can define another point based on knowing the slope.<BR>\n" );
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document.write( "m=5 means when we add 1 to x, the result is 5 being added to y.<BR>\n" );
document.write( "Let's do just that:  (4+1, 4+5) would do so.<BR>\n" );
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document.write( "Now we have two points:  (4,4) and (5,9).<BR>\n" );
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document.write( "Does y= 5x -16 work for the point (5,9)?<BR>\n" );
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document.write( "9 = 5(5) - 16<BR>\n" );
document.write( "9 = 25 - 16<BR>\n" );
document.write( "True.<BR>\n" );
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document.write( "We also are informed by graphing the line.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0Agraph%28500%2C500%2C-20%2C20%2C-20%2C20%2C5%2Ax-16%29%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0Agraph%28500%2C500%2C-20%2C20%2C-20%2C20%2C5%2Ax-16%29%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Looking at the graph reminds us to check the point ( ?, 0).<BR>\n" );
document.write( "0 = 5x - 16<BR>\n" );
document.write( "5x = 16<BR>\n" );
document.write( "x = 3.2<BR>\n" );
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document.write( "Inspecting the graph shows that looks right.<BR>\n" );
document.write( "Done. </SPAN>\n" );
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