Question

19. Solve for r: C=2pi r
A) R=C/2pi
B) R=2Cpi
C) R=2pi/C
D) R=1/2Cpi

Answer 1

The correct answer is:  [A]:  " {r = C /  2 pi} " .
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Explanation:
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Given:
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  " C = 2 * pi * r "  ;  isolate "r" on one side of the equation ; 

Divide EACH SIDE of the equation by:  "2 * pi " ;

C / (2 * pi)  = (2 * pi * r) / (2 * pi) ;

C / (2 * pi) = r ; 

↔  r = C / (2 * pi) ;  which is:  Answer choice:  [A]:  " {r = C /  2 pi} " .
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