document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=464457>Question 464457</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me solve this problem.... thank you\r<BR>\n" );
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document.write( "A parabola has its axis parallel to the y-axis and contains the points (1,-1),(2,3) and (3,15). Find its equation. (HINT: An equation of such a parabola is in the form: y= ax^2 + bx + c ). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #318741 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=318741\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A parabola has its axis parallel to the y-axis and contains the points (1,-1),(2,3) and (3,15). Find its equation.<BR>\n" );
document.write( "...<BR>\n" );
document.write( "Ax^2+Bx+C=y<BR>\n" );
document.write( "A(1^2)+B(1)+C=-1<BR>\n" );
document.write( "A(2^2)+B(2)+C=3<BR>\n" );
document.write( "A(3^2)+B(3)+C=15<BR>\n" );
document.write( "..<BR>\n" );
document.write( "1) A+B+C=-1<BR>\n" );
document.write( "2) 4A+2B+C=3<BR>\n" );
document.write( "3) 9A+3B+C=15<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2) 4A+2B+C=3<BR>\n" );
document.write( "1) A+B+C=-1<BR>\n" );
document.write( "Subtract eq 1 fm eq 2 to eliminate C<BR>\n" );
document.write( "4) 3A+B=4<BR>\n" );
document.write( "..<BR>\n" );
document.write( "3) 9A+3B+C=15<BR>\n" );
document.write( "2) 4A+2B+C=3<BR>\n" );
document.write( "subtract eq 2 fm eq 3 to eliminate C<BR>\n" );
document.write( "5) 5A+B=12<BR>\n" );
document.write( "4) 3A+B=4<BR>\n" );
document.write( "subtract eq 4 fm eq 5 to eliminate B<BR>\n" );
document.write( "2A=8<BR>\n" );
document.write( "A=4<BR>\n" );
document.write( "..<BR>\n" );
document.write( "4) 3A+B=4<BR>\n" );
document.write( "sub A<BR>\n" );
document.write( "3(4)+B=4<BR>\n" );
document.write( "B=4-12=-8<BR>\n" );
document.write( "..<BR>\n" );
document.write( "1) A+B+C=-1<BR>\n" );
document.write( "sub A and B<BR>\n" );
document.write( "4-8+C=-1<BR>\n" );
document.write( "C=3<BR>\n" );
document.write( "..<BR>\n" );
document.write( "Check:<BR>\n" );
document.write( "2) 4A+2B+C=3<BR>\n" );
document.write( "4(4)+2(-8)+3=3<BR>\n" );
document.write( "..<BR>\n" );
document.write( "3) 9A+3B+C=15<BR>\n" );
document.write( "9(4)+3(-8)+3=15<BR>\n" );
document.write( "..<BR>\n" );
document.write( "A=4<BR>\n" );
document.write( "B=-8<BR>\n" );
document.write( "C=3<BR>\n" );
document.write( "Equation:y=4x^2-8x+3 </SPAN>\n" );
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