document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189356>Question 1189356</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Find the equation of the circle whose center is on the line 2x  -  y + 4 = 0 and which passes thru the points (0,4) <BR>\n" );
document.write( "and (3,7)<BR>\n" );
document.write( "a. (x-7)^2 + (y-3)^2 = 8 <BR>\n" );
document.write( "b. (x-2)^2 + (y-3)^2 = 7 <BR>\n" );
document.write( "c. (x-7)^2 + (y-4)^2 = 6 <BR>\n" );
document.write( "d. (x-1)^2 + (y-6)^2 = 5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #820701 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=820701\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Find the equation of the circle whose center is on the line 2x - y + 4 = 0 and which passes thru the points A(0,4) and B(3,7)<BR>\n" );
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document.write( "The slope of AB is +1.<BR>\n" );
document.write( "The center has to be on the perpendicular bisector of the line thru the 2 points.<BR>\n" );
document.write( "The midpoint of AB is (1.5,5.5) and it's slope is -1.<BR>\n" );
document.write( "y-5.5 = -1*(x-1.5) = -x + 1.5<BR>\n" );
document.write( "y = -x + 7<BR>\n" );
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document.write( "The center is the intersection of the 2 lines.<BR>\n" );
document.write( "2x - y + 4 = 0<BR>\n" );
document.write( "y = 2x+4<BR>\n" );
document.write( "y = -x + 7<BR>\n" );
document.write( "---<BR>\n" );
document.write( "2x+4 = -x+7<BR>\n" );
document.write( "3x = 3<BR>\n" );
document.write( "x = 1, y = 6 ----> center is (1,6)<BR>\n" );
document.write( "r = the distance from the center to either point.<BR>\n" );
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document.write( "Choice d.  r = 5<BR>\n" );
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document.write( "There's no good reason for having 4 (or any #) of choices.<BR>\n" );
document.write( "The problem should be, \"Find the equation of the circle.\" </SPAN>\n" );
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