L=U²A divided by (A+B)² make A the subject of formular

A =  [- 2Bl + U^2 +/- √((2BL - U^2)^2 - 4B^2L^2) ] / 2L

Step-by-step explanation:

L = U^2A  / (A + B)^2

U^2 A = L(A^2 + 2AB + B^2)

U^2 A = LA^2 + 2ABL + B^2L

LA^2 + 2ABL - U^2A + B^2 L = 0

LA^2 + (2BL - U^2)A + B^2L = 0

Using the quadratic formula

A =  [- (2BL - U^2) +/- √[(2BL - U^2)^2 - 4*L*B^2L] / 2L

A =  [- 2BL + U^2 +/- √[(2BL - U^2)^2 - 4B^2L^2) ] / 2L

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step-by-step explanation:

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step-by-step explanation: