document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1148559>Question 1148559</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In the diagram below, EFGH is a rhombus formed by connecting the mid-points of the sides of the rectangle ABCD. The rectangle is circumscribed by the circle with center O. Find the area, in cm2 of the rhombus if OF=15cm, and JH=6cm. \r<BR>\n" );
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document.write( "Diagram: https://ibb.co/rwnM6f9 </SPAN>\n" );
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document.write( "FK = JH = 6, so the radius of the circle is OF+FK = OF+JH = 21.<br><BR>\n" );
document.write( "OC is also a radius of the circle, so OC = 21.<br><BR>\n" );
document.write( "Then triangle OFC is a right triangle and we know OF=15 and OC=21; the Pythagorean Theorem then tells us<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=FC+=+sqrt%2821%5E2-15%5E2%29+=+sqrt%28441-225%29+=+sqrt%28216%29+=+6%2Asqrt%286%29 ALIGN=MIDDLE  ALT=\"FC+=+sqrt%2821%5E2-15%5E2%29+=+sqrt%28441-225%29+=+sqrt%28216%29+=+6%2Asqrt%286%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Then the diagonals of the rhombus are 30 and 12*sqrt(6).<br><BR>\n" );
document.write( "The area of a rhombus is half the product of the diagonals:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+%281%2F2%29%2830%29%2812%2Asqrt%286%29%29+=+180%2Asqrt%286%29 ALIGN=MIDDLE  ALT=\"A+=+%281%2F2%29%2830%29%2812%2Asqrt%286%29%29+=+180%2Asqrt%286%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
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