document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=760510>Question 760510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> y varies directly as the square of x. If y=80 when x=20. Find y when x=90 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #462689 by </B><A HREF=/tutors/aboutme.mpl?userid=ramkikk66><B>ramkikk66(644)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ramkikk66><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=462689\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y varies directly as the square of x. This means that the ratio of y to x^2 is a constant. Let us call it k. Mathematically,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28y+%2F+x%5E2%29+=+k+ ALIGN=MIDDLE  ALT=\"%28y+%2F+x%5E2%29+=+k+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "y = 80 when x = 20. Substituting for y and x in the above equation,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+80+%2F+20%5E2+=+k+ ALIGN=MIDDLE  ALT=\"+80+%2F+20%5E2+=+k+\"   DISABLED_style= \"max-width:90%; height:auto;\" > or\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+k+=+80+%2F+400+=+0.2+ ALIGN=MIDDLE  ALT=\"+k+=+80+%2F+400+=+0.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So when x = 90, \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+%2F+90%5E2+=+k+=+0.2+ ALIGN=MIDDLE  ALT=\"+y+%2F+90%5E2+=+k+=+0.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Therefore, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+90%5E2+%2A+0.2+=+8100+%2A+0.2+ ALIGN=MIDDLE  ALT=\"+y+=+90%5E2+%2A+0.2+=+8100+%2A+0.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+1620+ ALIGN=MIDDLE  ALT=\"+y+=+1620+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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