document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=389461>Question 389461</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to find the x intercept of this equation. I just dont get any of it. \r<BR>\n" );
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document.write( "4x+5y=8 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #275993 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=275993\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It sounds like you're having a tough time with algebra, huh?<BR>\n" );
document.write( "Let's see if I can explain how to do this problem.<BR>\n" );
document.write( "Find the x-intercept of:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B5y+=+8 ALIGN=MIDDLE  ALT=\"4x%2B5y+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "When you graph this \"linear\" equation (I'll do that in a bit), you get a straight line. This is why we call this a \"linear\" equation.<BR>\n" );
document.write( "Now this straight line may cross or intercept the x-axis (of course, it may also intercept the y-axis).<BR>\n" );
document.write( "You are being asked to find the value of the x-coordinate of the point on the x-axis where this line crosses it.<BR>\n" );
document.write( "There are a couple of ways to do this.<BR>\n" );
document.write( "Graph the equation and inspect the graph for the crossing point. Let's do that now.<BR>\n" );
document.write( "First we need to get this equation into the \"slope-intercept\" form: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+mx%2Bb ALIGN=MIDDLE  ALT=\"y+=+mx%2Bb\"   DISABLED_style= \"max-width:90%; height:auto;\" > where m is the slope of the line and b is the y-intercept.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B5y+=+8 ALIGN=MIDDLE  ALT=\"4x%2B5y+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > We need to get the y all by itself on the left side so first subtract 4x from both sides of the equation.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x-4x%2B5y+=+-4x%2B8 ALIGN=MIDDLE  ALT=\"4x-4x%2B5y+=+-4x%2B8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5y+=+-4x%2B8 ALIGN=MIDDLE  ALT=\"5y+=+-4x%2B8\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now divide both sides by 5 to isolate the y.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5y%2F5+=+%28-4%2F5%29x%2B8%2F5 ALIGN=MIDDLE  ALT=\"5y%2F5+=+%28-4%2F5%29x%2B8%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y+=+%28-4%2F5%29x%2B8%2F5%29 ALIGN=MIDDLE  ALT=\"highlight%28y+=+%28-4%2F5%29x%2B8%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now we can graph this equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C400%2C-5%2C5%2C-5%2C5%2C%28-4%2F5%29x%2B8%2F5%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C400%2C-5%2C5%2C-5%2C5%2C%28-4%2F5%29x%2B8%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "Now you can see from the graph that the line intersects the x-axis at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x+=+2%29 ALIGN=MIDDLE  ALT=\"highlight%28x+=+2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > so this is the x-intercept for this equation.<BR>\n" );
document.write( "The other way to find the x-intercept is to do it algebraically.<BR>\n" );
document.write( "You'll notice on the graph that x-axis crosses the y-axis at y = 0, so if we set y = 0 in the given equation and solve for x, we will have the x-intercept.<BR>\n" );
document.write( "Start with the given equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B5y+=+8 ALIGN=MIDDLE  ALT=\"4x%2B5y+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > Substitute y=0.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2B5%280%29+=+8 ALIGN=MIDDLE  ALT=\"4x%2B5%280%29+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x+=+8 ALIGN=MIDDLE  ALT=\"4x+=+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now divide both sides by 4.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x%2F4+=+8%2F4 ALIGN=MIDDLE  ALT=\"4x%2F4+=+8%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x+=+2%29 ALIGN=MIDDLE  ALT=\"highlight%28x+=+2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "I hope this helps! </SPAN>\n" );
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