document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1034164>Question 1034164</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The quadratic function which takes the value 41 when x=-2 and the value 20 at x=5 is y=ax^2-bx+c.Need help in finding values for a,b,c </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #648778 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=648778\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I would use ax^2+bx+c as the function, which will allow the b to be both positive or negative.<BR>\n" );
document.write( "4a-2b+c=41<BR>\n" );
document.write( "25a+5b+c=20<BR>\n" );
document.write( "subtract the second from the first<BR>\n" );
document.write( "-21a-7b=21<BR>\n" );
document.write( "divide by 7, both sides<BR>\n" );
document.write( "-3a-b=3<BR>\n" );
document.write( "b=-3a-3=-3(a+1)<BR>\n" );
document.write( "go back to original equations<BR>\n" );
document.write( "4a+6(a+1)+c=41<BR>\n" );
document.write( "25a-15(a+1)+c=20<BR>\n" );
document.write( "subtract again<BR>\n" );
document.write( "-21a+9(a+1)=21<BR>\n" );
document.write( "-21a+9a+9=21<BR>\n" );
document.write( "-12a=12<BR>\n" );
document.write( "a=-1<BR>\n" );
document.write( "b=0<BR>\n" );
document.write( "c=45<BR>\n" );
document.write( "y=-x^2+45<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );