document.write( "Question 968360: A central angle of 140º subtends an arc of length 10 feet on a circle. Find the radius of the circle\r
\n" ); document.write( "\n" ); document.write( "Please explain\r
\n" ); document.write( "\n" ); document.write( "Thank you \n" ); document.write( "
Algebra.Com's Answer #591745 by stanbon(75887)\"\" \"About 
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A central angle of 140º subtends an arc of length 10 feet on a circle. Find the radius of the circle
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\n" ); document.write( "140 degrees = 140(pi/180) = (7/9)pi radians
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\n" ); document.write( "Equation:
\n" ); document.write( "theta in radians = (arc length)/(radius)
\n" ); document.write( "(7/9)pi = 10/radius
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\n" ); document.write( "radius = 10/[(7/9)pi] = 90/(7pi) is approximately 4.09 ft
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\n" ); document.write( "Another way to work it using proportions::\r
\n" ); document.write( "\n" ); document.write( "circum/360 = arc/central angle
\n" ); document.write( "cir/360 = 10/140
\n" ); document.write( "cir = 3600/140 = 25.71
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\n" ); document.write( "2*pi*r = 25.71
\n" ); document.write( "radius = 25.71/(2*pi) = 4.09 ft.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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