The 'Algebrator' has solved the equation A = (a + b)/2 for the variable 'b' and returned the following solution:

b = 2A - b

A = (a + b)/2 multiply both sides by 2

2A = a + b

a + b = 2A subtract 'a' from both sides

a + b - a = 2A - a

b = 2A - a

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