document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169204>Question 1169204</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The power, P watts, supplied to a circuit by a 9-V battery is given by the formula p = -0.51^2 + 91 , where I is the current in amperes. (Amperes is just the units for the current, just like a length is in cm)\r<BR>\n" );
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document.write( "A)Graph the function.\r<BR>\n" );
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document.write( "b)For what value of the current with the power be a maximum?\r<BR>\n" );
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document.write( "c)What is the maximum power?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #793827 by </B><A HREF=/tutors/aboutme.mpl?userid=Solver92311><B>Solver92311(821)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Solver92311><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=Solver92311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=793827\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "You have a quadratic function with a negative lead coefficient, so the graph is a concave down parabola.  Therefore, the value of the function at the vertex is the maximum value of the function. The value of the independent variable at the vertex of a parabola is given by the additive inverse of the first-degree term coefficient divided by 2 times the lead coefficient.  Evaluate the function at the value of the independent variable at the vertex to find the maximum value of the function.  You can do your own arithmetic.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it<BR>\n" );
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document.write( "From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> <BR>\n" );
document.write( "I > Ø<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \ \\r\"> </SPAN>\n" );
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