Question 231461
Equation 1. b = ea/m 
Equation 2. a = mf^2 
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Solve either eqn for m, then sub into the other one.
Equation 1. b = ea/m 
m = ea/b
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Equation 2. a = mf^2 
a = (ea/b)*f^2
a = (eaf^2)/b
ef^2/b = 1
b = ef^2