document.write( "Question 136990: Inside a semicircular tunnel of diameter 20 feet, a vertical support beam is placed 6 feet from the side of the tunnel. How tall is the beam?\r
\n" ); document.write( "\n" ); document.write( "I tried using the pythagorean theorem. Since the beam hits the diameter at a 90 degree angle. I use 6^2+x^2=90^2 \r
\n" ); document.write( "\n" ); document.write( "I did not get any of the choices. I guessed by looking at the picture that the answer is less than the diameter but greater that the distance from the side. I got 9.2 ft. \n" ); document.write( "
Algebra.Com's Answer #100257 by scott8148(6628)\"\" \"About 
You can put this solution on YOUR website!
a triangle inscribed in a semicircle is a right triangle, with the diameter as the hypotenuse\r
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\n" ); document.write( "\n" ); document.write( "the beam divides the large triangle (ends of diameter and top of beam) into two smaller triangles
\n" ); document.write( "__ these smaller triangles are similar to the large triangle (and also to each other)\r
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\n" ); document.write( "\n" ); document.write( "let x=\"height of beam\" __ using ratios of similar triangles __ x:6::14:x\r
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\n" ); document.write( "\n" ); document.write( "x/6=14/x __ \"cross\" multiplying __ x^2=84 __ x=sqrt(84) \n" ); document.write( "
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