document.write( "Question 992491: Express the area A of a circle as a function of (a) it's radius r and (b) it's diameter d. \n" ); document.write( "
Algebra.Com's Answer #612101 by rothauserc(4718)\"\" \"About 
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Area of circle(A) = pi * r^2 where r is radius and pi is approx 3.14
\n" ); document.write( "Diameter(D) of circle = 2 * r
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\n" ); document.write( "a) A = pi * r^2
\n" ); document.write( "b) A = pi * (D/2)
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