document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=82527>Question 82527</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two parallel chords 16 cm and 30 cm long are 23cm apart.  What is the radius of the circle? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #59203 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=59203\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the center of the circle lies on the line connecting the midpoints of the chords, this line is also perpendicular to the chords\r<BR>\n" );
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document.write( "let x equal the distance from the center to the 30 cm chord, so 23-x equals the distance to the 16 cm chord\r<BR>\n" );
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document.write( "a right triangle is formed by x, half of the 30 cm chord and the radius\r<BR>\n" );
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document.write( "similarly, another right triangle is formed by 23-x, half of the 16 cm chord and the radius\r<BR>\n" );
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document.write( "using Pythagoras, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B15%5E2=r%5E2 ALIGN=MIDDLE  ALT=\"x%5E2%2B15%5E2=r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2823-x%29%5E2%2B8%5E2=r%5E2 ALIGN=MIDDLE  ALT=\"%2823-x%29%5E2%2B8%5E2=r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B225=529-46x%2Bx%5E2%2B64 ALIGN=MIDDLE  ALT=\"x%5E2%2B225=529-46x%2Bx%5E2%2B64\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... 225=593-46x ... x=8\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%5E2%2B15%5E2=r%5E2 ALIGN=MIDDLE  ALT=\"8%5E2%2B15%5E2=r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=289=r%5E2 ALIGN=MIDDLE  ALT=\"289=r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... r=17 cm </SPAN>\n" );
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