G=2b(R-r). Solve for r

Question

Hi, I need help how to solve for r 

Answer 1

G = 2b(R - r)

G = 2bR - 2br       distribute

G - 2bR = -2br      subtract 2bR from both sides

(G - 2bR)/-2b = r  divide both sides by -2b

 

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