document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=947367>Question 947367</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Problem: Determine whether the equation defines y as a function of x. Explain why or why not. \r<BR>\n" );
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document.write( "a.) x^2+y=9 \r<BR>\n" );
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document.write( "b.) x+sqrt(y)=5     </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #578028 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=578028\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Yes to both.\r<BR>\n" );
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document.write( "#1 is obvious because you solve for y in terms of x.\r<BR>\n" );
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document.write( "#2, less obvious.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2Bsqrt%28y%29=5 ALIGN=MIDDLE  ALT=\"x%2Bsqrt%28y%29=5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, one branch of a parabola.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28y%29=-x%2B5 ALIGN=MIDDLE  ALT=\"sqrt%28y%29=-x%2B5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you must have <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%3E=0 ALIGN=MIDDLE  ALT=\"y%3E=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "square both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%285-x%29%5E2 ALIGN=MIDDLE  ALT=\"y=%285-x%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, .\r<BR>\n" );
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document.write( "The part for which y is non-negative would be the actual graph.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-8%2C12%2C-8%2C12%2C%285-x%29%5E2%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-8%2C12%2C-8%2C12%2C%285-x%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Also multiply the right member.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=25-10x%2Bx%5E2 ALIGN=MIDDLE  ALT=\"y=25-10x%2Bx%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%5E2-10x%2B25 ALIGN=MIDDLE  ALT=\"y=x%5E2-10x%2B25\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and that is the same as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%28x-5%29%5E2 ALIGN=MIDDLE  ALT=\"y=%28x-5%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
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