document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1142065>Question 1142065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the equation of the circle with center in the first quadrant, with radius 2 and tangent to the y-axis at (0,1). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #762728 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=762728\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the general form of the equation for a circle is (x-h)^2 + (y-k)^2 = r^2\r<BR>\n" );
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document.write( "(h,k) is the center of the circle.\r<BR>\n" );
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document.write( "r is the radius of the circle.\r<BR>\n" );
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document.write( "the radius is 2, so the formula becomes (x-h)^2 + (y-k)^2 = 4\r<BR>\n" );
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document.write( "the y-axis is tangent to the circle at (0,1).\r<BR>\n" );
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document.write( "since the tangent point is on the circle, then the opposite point from that, going through the center of the circle, would be (4,1).\r<BR>\n" );
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document.write( "that's because the radius of the circle is perpendicular to the tangent to the circle at the point of tangency.\r<BR>\n" );
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document.write( "the diameter of the circles is extend to the other side of the circle, with the length of the diameter being equal to 2 times the length of the radius.\r<BR>\n" );
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document.write( "that makes the length of the diameter equal to 4.\r<BR>\n" );
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document.write( "the center of the circle if half the distance of the diameter.\r<BR>\n" );
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document.write( "the diameter extends from (0,1) to (4,1) in a direction that is parallel to the x-axis and perpendicular to the y-axis.\r<BR>\n" );
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document.write( "the center of the circle is halfway between the points (0,1) and (4,1).\r<BR>\n" );
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document.write( "that places it at (2,1).\r<BR>\n" );
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document.write( "the equation of the circle becomes (x-2)^2 + (y-1)^2 = 4\r<BR>\n" );
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document.write( "the graph of that equation looks like this.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2019/061002.jpg\" alt=\"$$$\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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